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Posted to user@cassandra.apache.org by "Steinmaurer, Thomas" <th...@dynatrace.com> on 2018/01/05 11:09:20 UTC
Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Hello,
has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure ...
Anybody else seeing a similar CPU increase?
Thanks,
Thomas
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freist?dterstra?e 313
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Erick Ramirez <fl...@gmail.com>.
Thanks for the insight, Romain, and providing those numbers. Looking
forward to others posting their stats here.
We are running up some tests and will share when available. Cheers!
On Sat, Jan 6, 2018 at 3:44 AM, Romain Hardouin <romainh_ml@yahoo.fr.invalid
> wrote:
> Hi,
>
> We also noticed an increase of CPU - both system and user - on our
> c3.4xlarge fleet.
> So far it's really visible with max(%user) and especially max(%system), it
> has doubled!
> I graphed a ratio "write/s / %system", it's interesting to see how the
> value dropped yesterday, you can see it here: https://ibb.co/dnVcHG
>
> For reference: https://aws.amazon.com/fr/security/security-bulletins/
> AWS-2018-013/
>
> Best,
>
> Romain
>
>
> Le vendredi 5 janvier 2018 à 13:09:35 UTC+1, Steinmaurer, Thomas <
> thomas.steinmaurer@dynatrace.com> a écrit :
>
>
> Hello,
>
>
>
> has anybody already some experience/results if a patched Linux kernel
> regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
>
>
>
> In production, all nodes running in AWS with m4.xlarge, we see up to a 50%
> relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018,
> most likely correlating with Amazon finished patching the underlying
> Hypervisor infrastructure …
>
>
>
> Anybody else seeing a similar CPU increase?
>
>
>
> Thanks,
>
> Thomas
>
>
> The contents of this e-mail are intended for the named addressee only. It
> contains information that may be confidential. Unless you are the named
> addressee or an authorized designee, you may not copy or use it, or
> disclose it to anyone else. If you received it in error please notify us
> immediately and then destroy it. Dynatrace Austria GmbH (registration
> number FN 91482h) is a company registered in Linz whose registered office
> is at 4040 Linz, Austria, Freistädterstraße 313
> <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
>
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Romain Hardouin <ro...@yahoo.fr.INVALID>.
Hi,
We also noticed an increase of CPU - both system and user - on our c3.4xlarge fleet. So far it's really visible with max(%user) and especially max(%system), it has doubled!I graphed a ratio "write/s / %system", it's interesting to see how the value dropped yesterday, you can see it here: https://ibb.co/dnVcHG
For reference: https://aws.amazon.com/fr/security/security-bulletins/AWS-2018-013/
Best,
Romain
Le vendredi 5 janvier 2018 à 13:09:35 UTC+1, Steinmaurer, Thomas <th...@dynatrace.com> a écrit :
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Hello,
has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure …
Anybody else seeing a similar CPU increase?
Thanks,
Thomas
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Dor Laor <do...@scylladb.com>.
Hard to tell from the first 10 google search results which Intel CPUs
has it so I went to ask my /proc/cpuinfo, turns out my >1 year Dell XPS
laptop has it. AWS's i3 has it too.
flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat
pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx pdpe1gb
rdtscp lm constant_tsc art arch_perfmon pebs bts rep_good nopl xtopology
nonstop_tsc cpuid aperfmperf tsc_known_freq pni pclmulqdq dtes64 monitor
ds_cpl vmx est tm2 ssse3 sdbg fma cx16 xtpr pdcm pcid sse4_1 sse4_2 x2apic
movbe popcnt tsc_deadline_timer aes xsave avx f16c rdrand lahf_lm abm
3dnowprefetch cpuid_fault epb invpcid_single pti intel_pt tpr_shadow vnmi
flexpriority ept vpid fsgsbase tsc_adjust bmi1 avx2 smep bmi2 erms invpcid
mpx rdseed adx smap clflushopt xsaveopt xsavec xgetbv1 xsaves dtherm ida
arat pln pts hwp hwp_notify hwp_act_window hwp_epp
On Tue, Jan 9, 2018 at 11:19 PM, daemeon reiydelle <da...@gmail.com>
wrote:
> Good luck with that. Pcid out since mid 2017 as I recall?
>
>
> Daemeon (Dæmœn) Reiydelle
> USA 1.415.501.0198 <(415)%20501-0198>
>
> On Jan 9, 2018 10:31 AM, "Dor Laor" <do...@scylladb.com> wrote:
>
> Make sure you pick instances with PCID cpu capability, their TLB overhead
> flush
> overhead is much smaller
>
> On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <
> thomas.steinmaurer@dynatrace.com> wrote:
>
>> Quick follow up.
>>
>>
>>
>> Others in AWS reporting/seeing something similar, e.g.:
>> https://twitter.com/BenBromhead/status/950245250504601600
>>
>>
>>
>> So, while we have seen an relative CPU increase of ~ 50% since Jan 4,
>> 2018, we now also have applied a kernel update at OS/VM level on a single
>> node (loadtest and not production though), thus more or less double patched
>> now. Additional CPU impact by OS/VM level kernel patching is more or less negligible,
>> so looks highly Hypervisor related.
>>
>>
>>
>> Regards,
>>
>> Thomas
>>
>>
>>
>> *From:* Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com]
>> *Sent:* Freitag, 05. Jänner 2018 12:09
>> *To:* user@cassandra.apache.org
>> *Subject:* Meltdown/Spectre Linux patch - Performance impact on
>> Cassandra?
>>
>>
>>
>> Hello,
>>
>>
>>
>> has anybody already some experience/results if a patched Linux kernel
>> regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
>>
>>
>>
>> In production, all nodes running in AWS with m4.xlarge, we see up to a
>> 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018,
>> most likely correlating with Amazon finished patching the underlying
>> Hypervisor infrastructure …
>>
>>
>>
>> Anybody else seeing a similar CPU increase?
>>
>>
>>
>> Thanks,
>>
>> Thomas
>>
>>
>>
>> The contents of this e-mail are intended for the named addressee only. It
>> contains information that may be confidential. Unless you are the named
>> addressee or an authorized designee, you may not copy or use it, or
>> disclose it to anyone else. If you received it in error please notify us
>> immediately and then destroy it. Dynatrace Austria GmbH (registration
>> number FN 91482h) is a company registered in Linz whose registered office
>> is at 4040 Linz, Austria, Freistädterstraße 313
>> <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
>> The contents of this e-mail are intended for the named addressee only. It
>> contains information that may be confidential. Unless you are the named
>> addressee or an authorized designee, you may not copy or use it, or
>> disclose it to anyone else. If you received it in error please notify us
>> immediately and then destroy it. Dynatrace Austria GmbH (registration
>> number FN 91482h) is a company registered in Linz whose registered office
>> is at 4040 Linz, Austria, Freistädterstraße 313
>> <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
>>
>
>
>
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Jeff Jirsa <jj...@gmail.com>.
Longer than that. Years. Check /proc/cpuinfo
--
Jeff Jirsa
> On Jan 9, 2018, at 11:19 PM, daemeon reiydelle <da...@gmail.com> wrote:
>
> Good luck with that. Pcid out since mid 2017 as I recall?
>
>
> Daemeon (Dæmœn) Reiydelle
> USA 1.415.501.0198
>
> On Jan 9, 2018 10:31 AM, "Dor Laor" <do...@scylladb.com> wrote:
> Make sure you pick instances with PCID cpu capability, their TLB overhead flush
> overhead is much smaller
>
>> On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <th...@dynatrace.com> wrote:
>> Quick follow up.
>>
>>
>>
>> Others in AWS reporting/seeing something similar, e.g.: https://twitter.com/BenBromhead/status/950245250504601600
>>
>>
>>
>> So, while we have seen an relative CPU increase of ~ 50% since Jan 4, 2018, we now also have applied a kernel update at OS/VM level on a single node (loadtest and not production though), thus more or less double patched now. Additional CPU impact by OS/VM level kernel patching is more or less negligible, so looks highly Hypervisor related.
>>
>>
>>
>> Regards,
>>
>> Thomas
>>
>>
>>
>> From: Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com]
>> Sent: Freitag, 05. Jänner 2018 12:09
>> To: user@cassandra.apache.org
>> Subject: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
>>
>>
>>
>> Hello,
>>
>>
>>
>> has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
>>
>>
>>
>> In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure …
>>
>>
>>
>> Anybody else seeing a similar CPU increase?
>>
>>
>>
>> Thanks,
>>
>> Thomas
>>
>>
>>
>> The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313
>>
>> The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313
>
>
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by daemeon reiydelle <da...@gmail.com>.
Good luck with that. Pcid out since mid 2017 as I recall?
Daemeon (Dæmœn) Reiydelle
USA 1.415.501.0198
On Jan 9, 2018 10:31 AM, "Dor Laor" <do...@scylladb.com> wrote:
Make sure you pick instances with PCID cpu capability, their TLB overhead
flush
overhead is much smaller
On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <
thomas.steinmaurer@dynatrace.com> wrote:
> Quick follow up.
>
>
>
> Others in AWS reporting/seeing something similar, e.g.:
> https://twitter.com/BenBromhead/status/950245250504601600
>
>
>
> So, while we have seen an relative CPU increase of ~ 50% since Jan 4,
> 2018, we now also have applied a kernel update at OS/VM level on a single
> node (loadtest and not production though), thus more or less double patched
> now. Additional CPU impact by OS/VM level kernel patching is more or less negligible,
> so looks highly Hypervisor related.
>
>
>
> Regards,
>
> Thomas
>
>
>
> *From:* Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com]
> *Sent:* Freitag, 05. Jänner 2018 12:09
> *To:* user@cassandra.apache.org
> *Subject:* Meltdown/Spectre Linux patch - Performance impact on Cassandra?
>
>
>
> Hello,
>
>
>
> has anybody already some experience/results if a patched Linux kernel
> regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
>
>
>
> In production, all nodes running in AWS with m4.xlarge, we see up to a 50%
> relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018,
> most likely correlating with Amazon finished patching the underlying
> Hypervisor infrastructure …
>
>
>
> Anybody else seeing a similar CPU increase?
>
>
>
> Thanks,
>
> Thomas
>
>
>
> The contents of this e-mail are intended for the named addressee only. It
> contains information that may be confidential. Unless you are the named
> addressee or an authorized designee, you may not copy or use it, or
> disclose it to anyone else. If you received it in error please notify us
> immediately and then destroy it. Dynatrace Austria GmbH (registration
> number FN 91482h) is a company registered in Linz whose registered office
> is at 4040 Linz, Austria, Freistädterstraße 313
> <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
> The contents of this e-mail are intended for the named addressee only. It
> contains information that may be confidential. Unless you are the named
> addressee or an authorized designee, you may not copy or use it, or
> disclose it to anyone else. If you received it in error please notify us
> immediately and then destroy it. Dynatrace Austria GmbH (registration
> number FN 91482h) is a company registered in Linz whose registered office
> is at 4040 Linz, Austria, Freistädterstraße 313
> <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
>
RE: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Carlos Rolo <ro...@pythian.com>.
We are seeing almost no impact on Azure (+1 or 2%). Non-patched OS.
On AWS we don't have any solid data yet.
On 13 Jan 2018 09:46, "Steinmaurer, Thomas" <
thomas.steinmaurer@dynatrace.com> wrote:
Hello Ben,
thanks for the notice. Similar here + others reporting as well:
https://blog.appoptics.com/visualizing-meltdown-aws/
Regards,
Thomas
*From:* Ben Slater [mailto:ben.slater@instaclustr.com]
*Sent:* Freitag, 12. Jänner 2018 23:37
*To:* user@cassandra.apache.org
*Subject:* Re: Meltdown/Spectre Linux patch - Performance impact on
Cassandra?
We’re seeing evidence across our fleet that AWS has rolled something out in
the last 24 hours that has significantly reduce the performance impacts -
back pretty close to pre-patch levels. Yet to see if the impacts come back
with o/s patching on top of the improved hypervisor.
Cheers
Ben
On Thu, 11 Jan 2018 at 05:32 Jon Haddad <jo...@jonhaddad.com> wrote:
For what it’s worth, we (TLP) just posted some results comparing pre and
post meltdown statistics: http://thelastpickle.com/blog/2018/
01/10/meltdown-impact-on-latency.html
On Jan 10, 2018, at 1:57 AM, Steinmaurer, Thomas <
thomas.steinmaurer@dynatrace.com> wrote:
m4.xlarge do have PCID to my knowledge, but possibly we need a rather new
kernel 4.14. But I fail to see how this could help anyway, cause this looks
highly Amazon Hypervisor patch related and we do not have the production
instances patched at OS/VM level (yet).
Thomas
*From:* Dor Laor [mailto:dor@scylladb.com <do...@scylladb.com>]
*Sent:* Dienstag, 09. Jänner 2018 19:30
*To:* user@cassandra.apache.org
*Subject:* Re: Meltdown/Spectre Linux patch - Performance impact on
Cassandra?
Make sure you pick instances with PCID cpu capability, their TLB overhead
flush
overhead is much smaller
On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <
thomas.steinmaurer@dynatrace.com> wrote:
Quick follow up.
Others in AWS reporting/seeing something similar, e.g.:https://twitter.com/
BenBromhead/status/950245250504601600
So, while we have seen an relative CPU increase of ~ 50% since Jan 4, 2018,
we now also have applied a kernel update at OS/VM level on a single node
(loadtest and not production though), thus more or less double patched now.
Additional CPU impact by OS/VM level kernel patching is more or less
negligible, so looks highly Hypervisor related.
Regards,
Thomas
*From:* Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com]
*Sent:* Freitag, 05. Jänner 2018 12:09
*To:* user@cassandra.apache.org
*Subject:* Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Hello,
has anybody already some experience/results if a patched Linux kernel
regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
In production, all nodes running in AWS with m4.xlarge, we see up to a 50%
relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018,
most likely correlating with Amazon finished patching the underlying
Hypervisor infrastructure …
Anybody else seeing a similar CPU increase?
Thanks,
Thomas
The contents of this e-mail are intended for the named addressee only. It
contains information that may be confidential. Unless you are the named
addressee or an authorized designee, you may not copy or use it, or
disclose it to anyone else. If you received it in error please notify us
immediately and then destroy it. Dynatrace Austria GmbH (registration
number FN 91482h) is a company registered in Linz whose registered office
is at 4040 Linz, Austria, Freistädterstraße 313
<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
The contents of this e-mail are intended for the named addressee only. It
contains information that may be confidential. Unless you are the named
addressee or an authorized designee, you may not copy or use it, or
disclose it to anyone else. If you received it in error please notify us
immediately and then destroy it. Dynatrace Austria GmbH (registration
number FN 91482h) is a company registered in Linz whose registered office
is at 4040 Linz, Austria, Freistädterstraße 313
<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
The contents of this e-mail are intended for the named addressee only. It
contains information that may be confidential. Unless you are the named
addressee or an authorized designee, you may not copy or use it, or
disclose it to anyone else. If you received it in error please notify us
immediately and then destroy it. Dynatrace Austria GmbH (registration
number FN 91482h) is a company registered in Linz whose registered office
is at 4040 Linz, Austria, Freistädterstraße 313
<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
--
*Ben Slater*
*Chief Product Officer*
* <https://www.instaclustr.com/>*
<https://www.facebook.com/instaclustr> <https://twitter.com/instaclustr>
<https://www.linkedin.com/company/instaclustr>
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immediately and then destroy it. Dynatrace Austria GmbH (registration
number FN 91482h) is a company registered in Linz whose registered office
is at 4040 Linz, Austria, Freistädterstraße 313
<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
--
--
RE: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by "Steinmaurer, Thomas" <th...@dynatrace.com>.
Hello Ben,
thanks for the notice. Similar here + others reporting as well: https://blog.appoptics.com/visualizing-meltdown-aws/
Regards,
Thomas
From: Ben Slater [mailto:ben.slater@instaclustr.com]
Sent: Freitag, 12. Jänner 2018 23:37
To: user@cassandra.apache.org
Subject: Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
We’re seeing evidence across our fleet that AWS has rolled something out in the last 24 hours that has significantly reduce the performance impacts - back pretty close to pre-patch levels. Yet to see if the impacts come back with o/s patching on top of the improved hypervisor.
Cheers
Ben
On Thu, 11 Jan 2018 at 05:32 Jon Haddad <jo...@jonhaddad.com>> wrote:
For what it’s worth, we (TLP) just posted some results comparing pre and post meltdown statistics: http://thelastpickle.com/blog/2018/01/10/meltdown-impact-on-latency.html
On Jan 10, 2018, at 1:57 AM, Steinmaurer, Thomas <th...@dynatrace.com>> wrote:
m4.xlarge do have PCID to my knowledge, but possibly we need a rather new kernel 4.14. But I fail to see how this could help anyway, cause this looks highly Amazon Hypervisor patch related and we do not have the production instances patched at OS/VM level (yet).
Thomas
From: Dor Laor [mailto:dor@scylladb.com]
Sent: Dienstag, 09. Jänner 2018 19:30
To: user@cassandra.apache.org<ma...@cassandra.apache.org>
Subject: Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Make sure you pick instances with PCID cpu capability, their TLB overhead flush
overhead is much smaller
On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <th...@dynatrace.com>> wrote:
Quick follow up.
Others in AWS reporting/seeing something similar, e.g.:https://twitter.com/BenBromhead/status/950245250504601600
So, while we have seen an relative CPU increase of ~ 50% since Jan 4, 2018, we now also have applied a kernel update at OS/VM level on a single node (loadtest and not production though), thus more or less double patched now. Additional CPU impact by OS/VM level kernel patching is more or less negligible, so looks highly Hypervisor related.
Regards,
Thomas
From: Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com<ma...@dynatrace.com>]
Sent: Freitag, 05. Jänner 2018 12:09
To: user@cassandra.apache.org<ma...@cassandra.apache.org>
Subject: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Hello,
has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure …
Anybody else seeing a similar CPU increase?
Thanks,
Thomas
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
--
Ben Slater
Chief Product Officer
[https://cdn2.hubspot.net/hubfs/2549680/Instaclustr-Navy-logo-new.png]<https://www.instaclustr.com/>
[http://cdn2.hubspot.net/hubfs/184235/dev_images/signature_app/facebook_sig.png]<https://www.facebook.com/instaclustr> [http://cdn2.hubspot.net/hubfs/184235/dev_images/signature_app/twitter_sig.png] <https://twitter.com/instaclustr> [http://cdn2.hubspot.net/hubfs/184235/dev_images/signature_app/linkedin_sig.png] <https://www.linkedin.com/company/instaclustr>
Read our latest technical blog posts here<https://www.instaclustr.com/blog/>.
This email has been sent on behalf of Instaclustr Pty. Limited (Australia) and Instaclustr Inc (USA).
This email and any attachments may contain confidential and legally privileged information. If you are not the intended recipient, do not copy or disclose its content, but please reply to this email immediately and highlight the error to the sender and then immediately delete the message.
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RE: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by "Steinmaurer, Thomas" <th...@dynatrace.com>.
Ben,
regarding OS/VM level patching impact. We see almost zero additional impact with 4.9.51-10.52.amzn1.x86_64 vs. 4.9.75-25.55.amzn1.x86_64 (https://alas.aws.amazon.com/ALAS-2018-939.html) on a m5.2xlarge. m5 instance type family is rather new and AWS told us to give them a try compared to m4, as they are running a different hypervisor technology etc.
Before the additional hypervisor patch on Jan 12, we saw a relative CPU improvement of ~ 29% at an advertised ECU improvement of 19%. With the additional Jan 12 AWS patching at hypervisor level (?), we see m5 vs. m4 almost at the same CPU level. So, m4 on XEN looks pretty good again. Same as before again (as you have already mentioned) + with the 2 mentioned kernels above in comparison, the situation looks, even with the additional OS/VM level patching. Thus, currently we do not see any further action items needed now.
Thomas
From: Ben Slater [mailto:ben.slater@instaclustr.com]
Sent: Freitag, 12. Jänner 2018 23:37
To: user@cassandra.apache.org
Subject: Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
We’re seeing evidence across our fleet that AWS has rolled something out in the last 24 hours that has significantly reduce the performance impacts - back pretty close to pre-patch levels. Yet to see if the impacts come back with o/s patching on top of the improved hypervisor.
Cheers
Ben
On Thu, 11 Jan 2018 at 05:32 Jon Haddad <jo...@jonhaddad.com>> wrote:
For what it’s worth, we (TLP) just posted some results comparing pre and post meltdown statistics: http://thelastpickle.com/blog/2018/01/10/meltdown-impact-on-latency.html
On Jan 10, 2018, at 1:57 AM, Steinmaurer, Thomas <th...@dynatrace.com>> wrote:
m4.xlarge do have PCID to my knowledge, but possibly we need a rather new kernel 4.14. But I fail to see how this could help anyway, cause this looks highly Amazon Hypervisor patch related and we do not have the production instances patched at OS/VM level (yet).
Thomas
From: Dor Laor [mailto:dor@scylladb.com]
Sent: Dienstag, 09. Jänner 2018 19:30
To: user@cassandra.apache.org<ma...@cassandra.apache.org>
Subject: Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Make sure you pick instances with PCID cpu capability, their TLB overhead flush
overhead is much smaller
On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <th...@dynatrace.com>> wrote:
Quick follow up.
Others in AWS reporting/seeing something similar, e.g.:https://twitter.com/BenBromhead/status/950245250504601600
So, while we have seen an relative CPU increase of ~ 50% since Jan 4, 2018, we now also have applied a kernel update at OS/VM level on a single node (loadtest and not production though), thus more or less double patched now. Additional CPU impact by OS/VM level kernel patching is more or less negligible, so looks highly Hypervisor related.
Regards,
Thomas
From: Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com<ma...@dynatrace.com>]
Sent: Freitag, 05. Jänner 2018 12:09
To: user@cassandra.apache.org<ma...@cassandra.apache.org>
Subject: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Hello,
has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure …
Anybody else seeing a similar CPU increase?
Thanks,
Thomas
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
--
Ben Slater
Chief Product Officer
[https://cdn2.hubspot.net/hubfs/2549680/Instaclustr-Navy-logo-new.png]<https://www.instaclustr.com/>
[http://cdn2.hubspot.net/hubfs/184235/dev_images/signature_app/facebook_sig.png]<https://www.facebook.com/instaclustr> [http://cdn2.hubspot.net/hubfs/184235/dev_images/signature_app/twitter_sig.png] <https://twitter.com/instaclustr> [http://cdn2.hubspot.net/hubfs/184235/dev_images/signature_app/linkedin_sig.png] <https://www.linkedin.com/company/instaclustr>
Read our latest technical blog posts here<https://www.instaclustr.com/blog/>.
This email has been sent on behalf of Instaclustr Pty. Limited (Australia) and Instaclustr Inc (USA).
This email and any attachments may contain confidential and legally privileged information. If you are not the intended recipient, do not copy or disclose its content, but please reply to this email immediately and highlight the error to the sender and then immediately delete the message.
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Ben Slater <be...@instaclustr.com>.
We’re seeing evidence across our fleet that AWS has rolled something out in
the last 24 hours that has significantly reduce the performance impacts -
back pretty close to pre-patch levels. Yet to see if the impacts come back
with o/s patching on top of the improved hypervisor.
Cheers
Ben
On Thu, 11 Jan 2018 at 05:32 Jon Haddad <jo...@jonhaddad.com> wrote:
> For what it’s worth, we (TLP) just posted some results comparing pre and
> post meltdown statistics:
> http://thelastpickle.com/blog/2018/01/10/meltdown-impact-on-latency.html
>
>
> On Jan 10, 2018, at 1:57 AM, Steinmaurer, Thomas <
> thomas.steinmaurer@dynatrace.com> wrote:
>
> m4.xlarge do have PCID to my knowledge, but possibly we need a rather new
> kernel 4.14. But I fail to see how this could help anyway, cause this looks
> highly Amazon Hypervisor patch related and we do not have the production
> instances patched at OS/VM level (yet).
>
> Thomas
>
> *From:* Dor Laor [mailto:dor@scylladb.com <do...@scylladb.com>]
> *Sent:* Dienstag, 09. Jänner 2018 19:30
> *To:* user@cassandra.apache.org
> *Subject:* Re: Meltdown/Spectre Linux patch - Performance impact on
> Cassandra?
>
> Make sure you pick instances with PCID cpu capability, their TLB overhead
> flush
> overhead is much smaller
>
> On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <
> thomas.steinmaurer@dynatrace.com> wrote:
>
> Quick follow up.
>
> Others in AWS reporting/seeing something similar, e.g.:
> https://twitter.com/BenBromhead/status/950245250504601600
>
> So, while we have seen an relative CPU increase of ~ 50% since Jan 4,
> 2018, we now also have applied a kernel update at OS/VM level on a single
> node (loadtest and not production though), thus more or less double patched
> now. Additional CPU impact by OS/VM level kernel patching is more or less
> negligible, so looks highly Hypervisor related.
>
> Regards,
> Thomas
>
> *From:* Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com]
> *Sent:* Freitag, 05. Jänner 2018 12:09
> *To:* user@cassandra.apache.org
> *Subject:* Meltdown/Spectre Linux patch - Performance impact on Cassandra?
>
> Hello,
>
> has anybody already some experience/results if a patched Linux kernel
> regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
>
> In production, all nodes running in AWS with m4.xlarge, we see up to a 50%
> relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018,
> most likely correlating with Amazon finished patching the underlying
> Hypervisor infrastructure …
>
> Anybody else seeing a similar CPU increase?
>
> Thanks,
> Thomas
>
> The contents of this e-mail are intended for the named addressee only. It
> contains information that may be confidential. Unless you are the named
> addressee or an authorized designee, you may not copy or use it, or
> disclose it to anyone else. If you received it in error please notify us
> immediately and then destroy it. Dynatrace Austria GmbH (registration
> number FN 91482h) is a company registered in Linz whose registered office
> is at 4040 Linz, Austria, Freistädterstraße 313
> <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
> The contents of this e-mail are intended for the named addressee only. It
> contains information that may be confidential. Unless you are the named
> addressee or an authorized designee, you may not copy or use it, or
> disclose it to anyone else. If you received it in error please notify us
> immediately and then destroy it. Dynatrace Austria GmbH (registration
> number FN 91482h) is a company registered in Linz whose registered office
> is at 4040 Linz, Austria, Freistädterstraße 313
> <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
>
>
> The contents of this e-mail are intended for the named addressee only. It
> contains information that may be confidential. Unless you are the named
> addressee or an authorized designee, you may not copy or use it, or
> disclose it to anyone else. If you received it in error please notify us
> immediately and then destroy it. Dynatrace Austria GmbH (registration
> number FN 91482h) is a company registered in Linz whose registered office
> is at 4040 Linz, Austria, Freistädterstraße 313
> <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
>
>
>
--
*Ben Slater*
*Chief Product Officer <https://www.instaclustr.com/>*
<https://www.facebook.com/instaclustr> <https://twitter.com/instaclustr>
<https://www.linkedin.com/company/instaclustr>
Read our latest technical blog posts here
<https://www.instaclustr.com/blog/>.
This email has been sent on behalf of Instaclustr Pty. Limited (Australia)
and Instaclustr Inc (USA).
This email and any attachments may contain confidential and legally
privileged information. If you are not the intended recipient, do not copy
or disclose its content, but please reply to this email immediately and
highlight the error to the sender and then immediately delete the message.
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Jon Haddad <jo...@jonhaddad.com>.
For what it’s worth, we (TLP) just posted some results comparing pre and post meltdown statistics: http://thelastpickle.com/blog/2018/01/10/meltdown-impact-on-latency.html <http://thelastpickle.com/blog/2018/01/10/meltdown-impact-on-latency.html>
> On Jan 10, 2018, at 1:57 AM, Steinmaurer, Thomas <th...@dynatrace.com> wrote:
>
> m4.xlarge do have PCID to my knowledge, but possibly we need a rather new kernel 4.14. But I fail to see how this could help anyway, cause this looks highly Amazon Hypervisor patch related and we do not have the production instances patched at OS/VM level (yet). <>
>
> Thomas
>
> From: Dor Laor [mailto:dor@scylladb.com]
> Sent: Dienstag, 09. Jänner 2018 19:30
> To: user@cassandra.apache.org
> Subject: Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
>
> Make sure you pick instances with PCID cpu capability, their TLB overhead flush
> overhead is much smaller
>
> On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <thomas.steinmaurer@dynatrace.com <ma...@dynatrace.com>> wrote:
> Quick follow up. <>
>
> Others in AWS reporting/seeing something similar, e.g.:https://twitter.com/BenBromhead/status/950245250504601600 <https://twitter.com/BenBromhead/status/950245250504601600>
>
> So, while we have seen an relative CPU increase of ~ 50% since Jan 4, 2018, we now also have applied a kernel update at OS/VM level on a single node (loadtest and not production though), thus more or less double patched now. Additional CPU impact by OS/VM level kernel patching is more or less negligible, so looks highly Hypervisor related.
>
> Regards,
> Thomas
>
> From: Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com <ma...@dynatrace.com>]
> Sent: Freitag, 05. Jänner 2018 12:09
> To: user@cassandra.apache.org <ma...@cassandra.apache.org>
> Subject: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
>
> Hello,
>
> has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
>
> In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure …
>
> Anybody else seeing a similar CPU increase?
>
> Thanks,
> Thomas
>
> The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313 <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
> The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313 <https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
>
> The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313
RE: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by "Steinmaurer, Thomas" <th...@dynatrace.com>.
m4.xlarge do have PCID to my knowledge, but possibly we need a rather new kernel 4.14. But I fail to see how this could help anyway, cause this looks highly Amazon Hypervisor patch related and we do not have the production instances patched at OS/VM level (yet).
Thomas
From: Dor Laor [mailto:dor@scylladb.com]
Sent: Dienstag, 09. Jänner 2018 19:30
To: user@cassandra.apache.org
Subject: Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Make sure you pick instances with PCID cpu capability, their TLB overhead flush
overhead is much smaller
On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <th...@dynatrace.com>> wrote:
Quick follow up.
Others in AWS reporting/seeing something similar, e.g.: https://twitter.com/BenBromhead/status/950245250504601600
So, while we have seen an relative CPU increase of ~ 50% since Jan 4, 2018, we now also have applied a kernel update at OS/VM level on a single node (loadtest and not production though), thus more or less double patched now. Additional CPU impact by OS/VM level kernel patching is more or less negligible, so looks highly Hypervisor related.
Regards,
Thomas
From: Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com<ma...@dynatrace.com>]
Sent: Freitag, 05. Jänner 2018 12:09
To: user@cassandra.apache.org<ma...@cassandra.apache.org>
Subject: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Hello,
has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure …
Anybody else seeing a similar CPU increase?
Thanks,
Thomas
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313<https://maps.google.com/?q=4040+Linz,+Austria,+Freist%C3%A4dterstra%C3%9Fe+313&entry=gmail&source=g>
The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Tony Anecito <ad...@yahoo.com.INVALID>.
Hi All,Has anyone seen any test results for SQL Server? Although I am a Cassandra user I do use SQL Server for other companies.
Thanks,-Tony
From: Dor Laor <do...@scylladb.com>
To: user@cassandra.apache.org
Sent: Tuesday, January 9, 2018 10:31 AM
Subject: Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Make sure you pick instances with PCID cpu capability, their TLB overhead flushoverhead is much smaller
On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <th...@dynatrace.com> wrote:
Quick follow up. Others in AWS reporting/seeing something similar, e.g.:https://twitter.com/ BenBromhead/status/ 950245250504601600 So, while we have seen an relative CPU increase of ~ 50% since Jan 4, 2018, we now also have applied a kernel update at OS/VM level on a single node (loadtest and not production though), thus more or less double patched now. Additional CPU impact by OS/VM level kernel patching is more or lessnegligible, so looks highly Hypervisor related. Regards,Thomas From: Steinmaurer, Thomas [mailto:thomas.steinmaurer@ dynatrace.com]
Sent: Freitag, 05. Jänner 2018 12:09
To: user@cassandra.apache.org
Subject: Meltdown/Spectre Linux patch - Performance impact on Cassandra? Hello, has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively? In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure … Anybody else seeing a similar CPU increase? Thanks,Thomas The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313The contents of this e-mail are intended for the named addressee only. It contains information that may be confidential. Unless you are the named addressee or an authorized designee, you may not copy or use it, or disclose it to anyone else. If you received it in error please notify us immediately and then destroy it. Dynatrace Austria GmbH (registration number FN 91482h) is a company registered in Linz whose registered office is at 4040 Linz, Austria, Freistädterstraße 313
Re: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by Dor Laor <do...@scylladb.com>.
Make sure you pick instances with PCID cpu capability, their TLB overhead
flush
overhead is much smaller
On Tue, Jan 9, 2018 at 2:04 AM, Steinmaurer, Thomas <
thomas.steinmaurer@dynatrace.com> wrote:
> Quick follow up.
>
>
>
> Others in AWS reporting/seeing something similar, e.g.:
> https://twitter.com/BenBromhead/status/950245250504601600
>
>
>
> So, while we have seen an relative CPU increase of ~ 50% since Jan 4,
> 2018, we now also have applied a kernel update at OS/VM level on a single
> node (loadtest and not production though), thus more or less double patched
> now. Additional CPU impact by OS/VM level kernel patching is more or less negligible,
> so looks highly Hypervisor related.
>
>
>
> Regards,
>
> Thomas
>
>
>
> *From:* Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com]
> *Sent:* Freitag, 05. Jänner 2018 12:09
> *To:* user@cassandra.apache.org
> *Subject:* Meltdown/Spectre Linux patch - Performance impact on Cassandra?
>
>
>
> Hello,
>
>
>
> has anybody already some experience/results if a patched Linux kernel
> regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
>
>
>
> In production, all nodes running in AWS with m4.xlarge, we see up to a 50%
> relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018,
> most likely correlating with Amazon finished patching the underlying
> Hypervisor infrastructure …
>
>
>
> Anybody else seeing a similar CPU increase?
>
>
>
> Thanks,
>
> Thomas
>
>
>
> The contents of this e-mail are intended for the named addressee only. It
> contains information that may be confidential. Unless you are the named
> addressee or an authorized designee, you may not copy or use it, or
> disclose it to anyone else. If you received it in error please notify us
> immediately and then destroy it. Dynatrace Austria GmbH (registration
> number FN 91482h) is a company registered in Linz whose registered office
> is at 4040 Linz, Austria, Freistädterstraße 313
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RE: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Posted by "Steinmaurer, Thomas" <th...@dynatrace.com>.
Quick follow up.
Others in AWS reporting/seeing something similar, e.g.: https://twitter.com/BenBromhead/status/950245250504601600
So, while we have seen an relative CPU increase of ~ 50% since Jan 4, 2018, we now also have applied a kernel update at OS/VM level on a single node (loadtest and not production though), thus more or less double patched now. Additional CPU impact by OS/VM level kernel patching is more or less negligible, so looks highly Hypervisor related.
Regards,
Thomas
From: Steinmaurer, Thomas [mailto:thomas.steinmaurer@dynatrace.com]
Sent: Freitag, 05. Jänner 2018 12:09
To: user@cassandra.apache.org
Subject: Meltdown/Spectre Linux patch - Performance impact on Cassandra?
Hello,
has anybody already some experience/results if a patched Linux kernel regarding Meltdown/Spectre is affecting performance of Cassandra negatively?
In production, all nodes running in AWS with m4.xlarge, we see up to a 50% relative (e.g. AVG CPU from 40% => 60%) CPU increase since Jan 4, 2018, most likely correlating with Amazon finished patching the underlying Hypervisor infrastructure ...
Anybody else seeing a similar CPU increase?
Thanks,
Thomas
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