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Posted to user@cassandra.apache.org by Darvin Denmian <da...@gmail.com> on 2012/08/08 04:34:30 UTC
Use of SSD for commitlog
Hi,
Can somebody tell me if is there some benefit in use SSD Disks
for commitlog?
THanks!
Re: Use of SSD for commitlog
Posted by Darvin Denmian <da...@gmail.com>.
Great !
On Wed, Aug 8, 2012 at 11:41 AM, Amit Kumar <ku...@gmail.com>wrote:
>
> There is a really good presentation about SSD and Cassandra on youtube by
> Rick Branson. I highly recommend watching it.
>
> http://www.youtube.com/watch?v=zQdDi9pdf3I
>
>
> Amit
> On Aug 8, 2012, at 6:23 AM, Hiller, Dean wrote:
>
> > A 7.5 is probably fine and can still beat it as it is going to be the
> speed of writing not seeking(and I am not sure if they spec hard drives
> with a write time when not seeking….not sure). Remember that drives are
> rated on how fast they spin…this disk should not be spinning a lot(in
> theory)…it is always writing.
> >
> > Even on a read, it would do one seek and then do a very long sequential
> read(and I think that only happens on startup anyways).
> >
> > Later,
> > Dean
> >
> > From: Darvin Denmian <darvin.denmian@gmail.com<mailto:
> darvin.denmian@gmail.com>>
> > Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>"
> <us...@cassandra.apache.org>>
> > Date: Wednesday, August 8, 2012 7:16 AM
> > To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <
> user@cassandra.apache.org<ma...@cassandra.apache.org>>
> > Subject: Re: Use of SSD for commitlog
> >
> > Thanks for your reply Dean,
> >
> > considering your reply.... maybe I use a 15k RPM SCSI Disk, I think
> it'll perform better than a SSD disk.
> >
> > On Wed, Aug 8, 2012 at 10:01 AM, Hiller, Dean <Dean.Hiller@nrel.gov
> <ma...@nrel.gov>> wrote:
> > Probably not since it is sequential writes….(ie. Seek performance is the
> big hit and if it is sequential it should not be seeking and is about just
> as fast as an SSD in theory). In practice, I have not measure the
> performance of one vs. the other though…that I always the best way to
> go.(you could write a micro benchmark test with warmup writes and then
> stream writes to and see how it does without cassandra).
> >
> > Dean
> >
> > From: Darvin Denmian <darvin.denmian@gmail.com<mailto:
> darvin.denmian@gmail.com><mailto:darvin.denmian@gmail.com<mailto:
> darvin.denmian@gmail.com>>>
> > Reply-To: "user@cassandra.apache.org<mailto:user@cassandra.apache.org
> ><ma...@cassandra.apache.org>>" <
> user@cassandra.apache.org<ma...@cassandra.apache.org><mailto:
> user@cassandra.apache.org<ma...@cassandra.apache.org>>>
> > Date: Tuesday, August 7, 2012 8:34 PM
> > To: "user@cassandra.apache.org<ma...@cassandra.apache.org><mailto:
> user@cassandra.apache.org<ma...@cassandra.apache.org>>" <
> user@cassandra.apache.org<ma...@cassandra.apache.org><mailto:
> user@cassandra.apache.org<ma...@cassandra.apache.org>>>
> > Subject: Use of SSD for commitlog
> >
> > Hi,
> >
> > Can somebody tell me if is there some benefit in use SSD Disks
> > for commitlog?
> >
> > THanks!
> >
>
>
Re: Use of SSD for commitlog
Posted by Terje Marthinussen <tm...@gmail.com>.
Probably you can get an intel 320 160GB or a Samsung 830 for the same price as the 146GB 15k rpm drive.
Overprovision the SSD 20% and off you go.
It will beat the HDD both sequentially and randomly.
Terje
On Aug 8, 2012, at 11:41 PM, Amit Kumar <ku...@gmail.com> wrote:
>
> There is a really good presentation about SSD and Cassandra on youtube by Rick Branson. I highly recommend watching it.
>
> http://www.youtube.com/watch?v=zQdDi9pdf3I
>
>
> Amit
> On Aug 8, 2012, at 6:23 AM, Hiller, Dean wrote:
>
>> A 7.5 is probably fine and can still beat it as it is going to be the speed of writing not seeking(and I am not sure if they spec hard drives with a write time when not seeking….not sure). Remember that drives are rated on how fast they spin…this disk should not be spinning a lot(in theory)…it is always writing.
>>
>> Even on a read, it would do one seek and then do a very long sequential read(and I think that only happens on startup anyways).
>>
>> Later,
>> Dean
>>
>> From: Darvin Denmian <da...@gmail.com>>
>> Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
>> Date: Wednesday, August 8, 2012 7:16 AM
>> To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
>> Subject: Re: Use of SSD for commitlog
>>
>> Thanks for your reply Dean,
>>
>> considering your reply.... maybe I use a 15k RPM SCSI Disk, I think it'll perform better than a SSD disk.
>>
>> On Wed, Aug 8, 2012 at 10:01 AM, Hiller, Dean <De...@nrel.gov>> wrote:
>> Probably not since it is sequential writes….(ie. Seek performance is the big hit and if it is sequential it should not be seeking and is about just as fast as an SSD in theory). In practice, I have not measure the performance of one vs. the other though…that I always the best way to go.(you could write a micro benchmark test with warmup writes and then stream writes to and see how it does without cassandra).
>>
>> Dean
>>
>> From: Darvin Denmian <da...@gmail.com>>>
>> Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>>" <us...@cassandra.apache.org>>>
>> Date: Tuesday, August 7, 2012 8:34 PM
>> To: "user@cassandra.apache.org<ma...@cassandra.apache.org>>" <us...@cassandra.apache.org>>>
>> Subject: Use of SSD for commitlog
>>
>> Hi,
>>
>> Can somebody tell me if is there some benefit in use SSD Disks
>> for commitlog?
>>
>> THanks!
>>
>
Re: Use of SSD for commitlog
Posted by Amit Kumar <ku...@gmail.com>.
There is a really good presentation about SSD and Cassandra on youtube by Rick Branson. I highly recommend watching it.
http://www.youtube.com/watch?v=zQdDi9pdf3I
Amit
On Aug 8, 2012, at 6:23 AM, Hiller, Dean wrote:
> A 7.5 is probably fine and can still beat it as it is going to be the speed of writing not seeking(and I am not sure if they spec hard drives with a write time when not seeking….not sure). Remember that drives are rated on how fast they spin…this disk should not be spinning a lot(in theory)…it is always writing.
>
> Even on a read, it would do one seek and then do a very long sequential read(and I think that only happens on startup anyways).
>
> Later,
> Dean
>
> From: Darvin Denmian <da...@gmail.com>>
> Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
> Date: Wednesday, August 8, 2012 7:16 AM
> To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
> Subject: Re: Use of SSD for commitlog
>
> Thanks for your reply Dean,
>
> considering your reply.... maybe I use a 15k RPM SCSI Disk, I think it'll perform better than a SSD disk.
>
> On Wed, Aug 8, 2012 at 10:01 AM, Hiller, Dean <De...@nrel.gov>> wrote:
> Probably not since it is sequential writes….(ie. Seek performance is the big hit and if it is sequential it should not be seeking and is about just as fast as an SSD in theory). In practice, I have not measure the performance of one vs. the other though…that I always the best way to go.(you could write a micro benchmark test with warmup writes and then stream writes to and see how it does without cassandra).
>
> Dean
>
> From: Darvin Denmian <da...@gmail.com>>>
> Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>>" <us...@cassandra.apache.org>>>
> Date: Tuesday, August 7, 2012 8:34 PM
> To: "user@cassandra.apache.org<ma...@cassandra.apache.org>>" <us...@cassandra.apache.org>>>
> Subject: Use of SSD for commitlog
>
> Hi,
>
> Can somebody tell me if is there some benefit in use SSD Disks
> for commitlog?
>
> THanks!
>
Re: Use of SSD for commitlog
Posted by "Hiller, Dean" <De...@nrel.gov>.
A 7.5 is probably fine and can still beat it as it is going to be the speed of writing not seeking(and I am not sure if they spec hard drives with a write time when not seeking….not sure). Remember that drives are rated on how fast they spin…this disk should not be spinning a lot(in theory)…it is always writing.
Even on a read, it would do one seek and then do a very long sequential read(and I think that only happens on startup anyways).
Later,
Dean
From: Darvin Denmian <da...@gmail.com>>
Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
Date: Wednesday, August 8, 2012 7:16 AM
To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
Subject: Re: Use of SSD for commitlog
Thanks for your reply Dean,
considering your reply.... maybe I use a 15k RPM SCSI Disk, I think it'll perform better than a SSD disk.
On Wed, Aug 8, 2012 at 10:01 AM, Hiller, Dean <De...@nrel.gov>> wrote:
Probably not since it is sequential writes….(ie. Seek performance is the big hit and if it is sequential it should not be seeking and is about just as fast as an SSD in theory). In practice, I have not measure the performance of one vs. the other though…that I always the best way to go.(you could write a micro benchmark test with warmup writes and then stream writes to and see how it does without cassandra).
Dean
From: Darvin Denmian <da...@gmail.com>>>
Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>>" <us...@cassandra.apache.org>>>
Date: Tuesday, August 7, 2012 8:34 PM
To: "user@cassandra.apache.org<ma...@cassandra.apache.org>>" <us...@cassandra.apache.org>>>
Subject: Use of SSD for commitlog
Hi,
Can somebody tell me if is there some benefit in use SSD Disks
for commitlog?
THanks!
Re: Use of SSD for commitlog
Posted by Darvin Denmian <da...@gmail.com>.
Thanks for your reply Dean,
considering your reply.... maybe I use a 15k RPM SCSI Disk, I think it'll
perform better than a SSD disk.
On Wed, Aug 8, 2012 at 10:01 AM, Hiller, Dean <De...@nrel.gov> wrote:
> Probably not since it is sequential writes….(ie. Seek performance is the
> big hit and if it is sequential it should not be seeking and is about just
> as fast as an SSD in theory). In practice, I have not measure the
> performance of one vs. the other though…that I always the best way to
> go.(you could write a micro benchmark test with warmup writes and then
> stream writes to and see how it does without cassandra).
>
> Dean
>
> From: Darvin Denmian <darvin.denmian@gmail.com<mailto:
> darvin.denmian@gmail.com>>
> Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <
> user@cassandra.apache.org<ma...@cassandra.apache.org>>
> Date: Tuesday, August 7, 2012 8:34 PM
> To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <
> user@cassandra.apache.org<ma...@cassandra.apache.org>>
> Subject: Use of SSD for commitlog
>
> Hi,
>
> Can somebody tell me if is there some benefit in use SSD Disks
> for commitlog?
>
> THanks!
>
Re: Use of SSD for commitlog
Posted by "Hiller, Dean" <De...@nrel.gov>.
Probably not since it is sequential writes….(ie. Seek performance is the big hit and if it is sequential it should not be seeking and is about just as fast as an SSD in theory). In practice, I have not measure the performance of one vs. the other though…that I always the best way to go.(you could write a micro benchmark test with warmup writes and then stream writes to and see how it does without cassandra).
Dean
From: Darvin Denmian <da...@gmail.com>>
Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
Date: Tuesday, August 7, 2012 8:34 PM
To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
Subject: Use of SSD for commitlog
Hi,
Can somebody tell me if is there some benefit in use SSD Disks
for commitlog?
THanks!