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Posted to user@accumulo.apache.org by "Moore, Matthew J." <MA...@saic.com> on 2012/09/11 18:02:29 UTC
Running Accumulo straight from Memory
Has anyone run Accumulo on a single server straight from memory?
Probably using something like a Fusion IO drive. We are trying to use
it without using an SSD or any spinning discs.
Matthew Moore
Systems Engineer
SAIC, ISBU
Columbia, MD
410-312-2542
Re: Running Accumulo straight from Memory
Posted by Eric Newton <er...@gmail.com>.
Accumulo needs something that provides the FileSystem interface. It also
needs to be distributed, replicated, and provide for a write-ahead log.
HDFS on a RAM disk pretty much gets you that.
On Tue, Sep 11, 2012 at 12:55 PM, Moore, Matthew J. <
MATTHEW.J.MOORE@saic.com> wrote:
> Have you tried it where you’re writing to straight block memory? Not
> using any file system or SATA controller.****
>
> ** **
>
> Matt****
>
>
> *Sent:* Tuesday, September 11, 2012 12:19 PM
> *To:* user@accumulo.apache.org
> *Subject:* Re: Running Accumulo straight from Memory****
>
> ** **
>
> I have run a small cluster with HDFS writing only to a RAM disk. Is that
> the sort of thing you are interested in?****
>
> ** **
>
> -Eric****
>
> On Tue, Sep 11, 2012 at 12:02 PM, Moore, Matthew J. <
> MATTHEW.J.MOORE@saic.com> wrote:****
>
> Has anyone run Accumulo on a single server straight from memory? Probably
> using something like a Fusion IO drive. We are trying to use it without
> using an SSD or any spinning discs.****
>
> ****
>
> *Matthew Moore*****
>
> Systems Engineer****
>
> SAIC, ISBU****
>
> Columbia, MD****
>
> 410-312-2542****
>
> ****
>
> ** **
>
RE: Running Accumulo straight from Memory
Posted by "Moore, Matthew J." <MA...@saic.com>.
Have you tried it where you're writing to straight block memory? Not
using any file system or SATA controller.
Matt
Sent: Tuesday, September 11, 2012 12:19 PM
To: user@accumulo.apache.org
Subject: Re: Running Accumulo straight from Memory
I have run a small cluster with HDFS writing only to a RAM disk. Is
that the sort of thing you are interested in?
-Eric
On Tue, Sep 11, 2012 at 12:02 PM, Moore, Matthew J.
<MA...@saic.com> wrote:
Has anyone run Accumulo on a single server straight from memory?
Probably using something like a Fusion IO drive. We are trying to use
it without using an SSD or any spinning discs.
Matthew Moore
Systems Engineer
SAIC, ISBU
Columbia, MD
410-312-2542
Re: Running Accumulo straight from Memory
Posted by Eric Newton <er...@gmail.com>.
I have run a small cluster with HDFS writing only to a RAM disk. Is that
the sort of thing you are interested in?
-Eric
On Tue, Sep 11, 2012 at 12:02 PM, Moore, Matthew J. <
MATTHEW.J.MOORE@saic.com> wrote:
> Has anyone run Accumulo on a single server straight from memory? Probably
> using something like a Fusion IO drive. We are trying to use it without
> using an SSD or any spinning discs.****
>
> ** **
>
> *Matthew Moore*****
>
> Systems Engineer****
>
> SAIC, ISBU****
>
> Columbia, MD****
>
> 410-312-2542****
>
> ** **
>
Re: Running Accumulo straight from Memory
Posted by David Medinets <da...@gmail.com>.
Have you looked at in-memory specific software like Lucene, VoltDB,
MySQL? Doesn't Accumulo have too much overhead to act primarily as an
in-memory datastore? What advantage do you see Accumulo having?
Re: Running Accumulo straight from Memory
Posted by Keith Turner <ke...@deenlo.com>.
On Wed, Sep 12, 2012 at 5:20 PM, David Medinets
<da...@gmail.com> wrote:
> Why would locality groups be useful in an in-memory system?
Memory is fast, yet we still organize data in memory to make it really
fast (e.g. hash maps, sorted maps, bloom filters, etc) Locality
groups are no different. If using that data organization will make
what you are attempting to do faster, then you would probably use it.
Assume you have two locality groups and one contains 1% of your data
by volume and the other 99%. Scanning just the locality group with
1% of the data will be faster than not having locality groups. It
cuts down on the amount of data you have to read and processes from
memory.
>
> On Wed, Sep 12, 2012 at 4:53 PM, Adam Fuchs <af...@apache.org> wrote:
>> Even if you are just using memory, minor and major compactions are important
>> to get compression, handle deletes, get sequential access (cache line
>> efficiency), use iterators, and introduce locality groups.
RE: Running Accumulo straight from Memory
Posted by "Moore, Matthew J." <MA...@saic.com>.
You guys are confirming what we predicted. This was a "like to have"
from our customer and we wanted to see if anyone else had tried this.
Thanks.
Matt
From: user-return-1336-MATTHEW.J.MOORE=saic.com@accumulo.apache.org
[mailto:user-return-1336-MATTHEW.J.MOORE=saic.com@accumulo.apache.org]
On Behalf Of Adam Fuchs
Sent: Wednesday, September 12, 2012 5:28 PM
To: user@accumulo.apache.org
Subject: Re: Running Accumulo straight from Memory
Yes, the effect of locality groups would be about the same in an in
memory system. The only exception would be if you're not using locality
groups and are fetching a particular column, the automatic seeking
behavior of the column filtering iterator would be more efficient with
in memory rfiles.
Adam
On Sep 12, 2012 5:20 PM, "David Medinets" <da...@gmail.com>
wrote:
Why would locality groups be useful in an in-memory system?
On Wed, Sep 12, 2012 at 4:53 PM, Adam Fuchs <af...@apache.org> wrote:
> Even if you are just using memory, minor and major compactions are
important
> to get compression, handle deletes, get sequential access (cache line
> efficiency), use iterators, and introduce locality groups.
Re: Running Accumulo straight from Memory
Posted by Adam Fuchs <af...@apache.org>.
Yes, the effect of locality groups would be about the same in an in memory
system. The only exception would be if you're not using locality groups and
are fetching a particular column, the automatic seeking behavior of the
column filtering iterator would be more efficient with in memory rfiles.
Adam
On Sep 12, 2012 5:20 PM, "David Medinets" <da...@gmail.com> wrote:
> Why would locality groups be useful in an in-memory system?
>
> On Wed, Sep 12, 2012 at 4:53 PM, Adam Fuchs <af...@apache.org> wrote:
> > Even if you are just using memory, minor and major compactions are
> important
> > to get compression, handle deletes, get sequential access (cache line
> > efficiency), use iterators, and introduce locality groups.
>
Re: Running Accumulo straight from Memory
Posted by David Medinets <da...@gmail.com>.
Why would locality groups be useful in an in-memory system?
On Wed, Sep 12, 2012 at 4:53 PM, Adam Fuchs <af...@apache.org> wrote:
> Even if you are just using memory, minor and major compactions are important
> to get compression, handle deletes, get sequential access (cache line
> efficiency), use iterators, and introduce locality groups.
RE: Running Accumulo straight from Memory
Posted by Adam Fuchs <af...@apache.org>.
Even if you are just using memory, minor and major compactions are
important to get compression, handle deletes, get sequential access (cache
line efficiency), use iterators, and introduce locality groups.
Adam
On Sep 12, 2012 12:33 PM, "Moore, Matthew J." <MA...@saic.com>
wrote:
> Adam,****
>
> It does look like we are the first to try this. We are trying to keep
> everything in memory and as a result there is no minor compactions, and
> probably major compactions to make tables larger. We tried this on SSDs
> using a file system and we were not getting the processing speeds that we
> had wanted.****
>
> ** **
>
> Matt****
>
> ** **
>
> ** **
>
> *From:* user-return-1330-MATTHEW.J.MOORE=saic.com@accumulo.apache.org[mailto:
> user-return-1330-MATTHEW.J.MOORE=saic.com@accumulo.apache.org] *On Behalf
> Of *Adam Fuchs
> *Sent:* Tuesday, September 11, 2012 5:30 PM
> *To:* user@accumulo.apache.org
> *Subject:* Re: Running Accumulo straight from Memory****
>
> ** **
>
> Matthew,****
>
> ** **
>
> I don't know of anyone who has done this, but I believe you could:****
>
> 1. mount a RAM disk****
>
> 2. point the hdfs core-site.xml fs.default.name property to file:///****
>
> 3. point the accumulo-site.xml instance.dfs.dir property to a directory on
> the RAM disk****
>
> 4. disable the WAL for all tables by setting the accumulo-site.xml
> table.walog.enabled to false****
>
> 5. initialize and start up accumulo as you regularly would and cross your
> fingers
>
> Of course, the "you may lose data" and "this is not an officially
> supported configuration" caveats apply. Out of curiosity, what would you be
> trying to accomplish with this configuration?****
>
> ** **
>
> Adam****
>
> ** **
>
> ** **
>
> On Tue, Sep 11, 2012 at 12:02 PM, Moore, Matthew J. <
> MATTHEW.J.MOORE@saic.com> wrote:****
>
> Has anyone run Accumulo on a single server straight from memory? Probably
> using something like a Fusion IO drive. We are trying to use it without
> using an SSD or any spinning discs.****
>
> ****
>
> *Matthew Moore*****
>
> Systems Engineer****
>
> SAIC, ISBU****
>
> Columbia, MD****
>
> 410-312-2542****
>
> ****
>
> ** **
>
Re: Running Accumulo straight from Memory
Posted by dl...@comcast.net.
Matt,
Did you see Eric Newton's response yesterday? Running on a ram disk has been done; however minor and major compactions will still occur.
- Dave
----- Original Message -----
From: "Matthew J. Moore" <MA...@saic.com>
To: user@accumulo.apache.org
Sent: Wednesday, September 12, 2012 12:32:31 PM
Subject: RE: Running Accumulo straight from Memory
Adam,
It does look like we are the first to try this. We are trying to keep everything in memory and as a result there is no minor compactions, and probably major compactions to make tables larger. We tried this on SSDs using a file system and we were not getting the processing speeds that we had wanted.
Matt
From: user-return-1330-MATTHEW.J.MOORE=saic.com@accumulo.apache.org [mailto:user-return-1330-MATTHEW.J.MOORE=saic.com@accumulo.apache.org] On Behalf Of Adam Fuchs
Sent: Tuesday, September 11, 2012 5:30 PM
To: user@accumulo.apache.org
Subject: Re: Running Accumulo straight from Memory
Matthew,
I don't know of anyone who has done this, but I believe you could:
1. mount a RAM disk
2. point the hdfs core-site.xml fs.default.name property to file:///
3. point the accumulo-site.xml instance.dfs.dir property to a directory on the RAM disk
4. disable the WAL for all tables by setting the accumulo-site.xml table.walog.enabled to false
5. initialize and start up accumulo as you regularly would and cross your fingers
Of course, the "you may lose data" and "this is not an officially supported configuration" caveats apply. Out of curiosity, what would you be trying to accomplish with this configuration?
Adam
On Tue, Sep 11, 2012 at 12:02 PM, Moore, Matthew J. < MATTHEW.J.MOORE@saic.com > wrote:
Has anyone run Accumulo on a single server straight from memory? Probably using something like a Fusion IO drive. We are trying to use it without using an SSD or any spinning discs.
Matthew Moore
Systems Engineer
SAIC, ISBU
Columbia, MD
410-312-2542
RE: Running Accumulo straight from Memory
Posted by "Moore, Matthew J." <MA...@saic.com>.
Adam,
It does look like we are the first to try this. We are trying to keep
everything in memory and as a result there is no minor compactions, and
probably major compactions to make tables larger. We tried this on SSDs
using a file system and we were not getting the processing speeds that
we had wanted.
Matt
From: user-return-1330-MATTHEW.J.MOORE=saic.com@accumulo.apache.org
[mailto:user-return-1330-MATTHEW.J.MOORE=saic.com@accumulo.apache.org]
On Behalf Of Adam Fuchs
Sent: Tuesday, September 11, 2012 5:30 PM
To: user@accumulo.apache.org
Subject: Re: Running Accumulo straight from Memory
Matthew,
I don't know of anyone who has done this, but I believe you could:
1. mount a RAM disk
2. point the hdfs core-site.xml fs.default.name
<http://fs.default.name/> property to file:///
3. point the accumulo-site.xml instance.dfs.dir property to a directory
on the RAM disk
4. disable the WAL for all tables by setting the accumulo-site.xml
table.walog.enabled to false
5. initialize and start up accumulo as you regularly would and cross
your fingers
Of course, the "you may lose data" and "this is not an officially
supported configuration" caveats apply. Out of curiosity, what would you
be trying to accomplish with this configuration?
Adam
On Tue, Sep 11, 2012 at 12:02 PM, Moore, Matthew J.
<MA...@saic.com> wrote:
Has anyone run Accumulo on a single server straight from memory?
Probably using something like a Fusion IO drive. We are trying to use
it without using an SSD or any spinning discs.
Matthew Moore
Systems Engineer
SAIC, ISBU
Columbia, MD
410-312-2542
Re: Running Accumulo straight from Memory
Posted by Adam Fuchs <af...@apache.org>.
Matthew,
I don't know of anyone who has done this, but I believe you could:
1. mount a RAM disk
2. point the hdfs core-site.xml fs.default.name property to file:///
3. point the accumulo-site.xml instance.dfs.dir property to a directory on
the RAM disk
4. disable the WAL for all tables by setting the accumulo-site.xml
table.walog.enabled to false
5. initialize and start up accumulo as you regularly would and cross your
fingers
Of course, the "you may lose data" and "this is not an officially supported
configuration" caveats apply. Out of curiosity, what would you be trying to
accomplish with this configuration?
Adam
On Tue, Sep 11, 2012 at 12:02 PM, Moore, Matthew J. <
MATTHEW.J.MOORE@saic.com> wrote:
> Has anyone run Accumulo on a single server straight from memory? Probably
> using something like a Fusion IO drive. We are trying to use it without
> using an SSD or any spinning discs.****
>
> ** **
>
> *Matthew Moore*****
>
> Systems Engineer****
>
> SAIC, ISBU****
>
> Columbia, MD****
>
> 410-312-2542****
>
> ** **
>
Re: Running Accumulo straight from Memory
Posted by William Slacum <wi...@accumulo.net>.
Woops- slow innurnet and didn't notice Eric's response.
On Tue, Sep 11, 2012 at 9:30 AM, William Slacum <
wilhelm.von.cloud@accumulo.net> wrote:
> You could mount a RAM disk and point HDFS to it.
>
>
> On Tue, Sep 11, 2012 at 9:02 AM, Moore, Matthew J. <
> MATTHEW.J.MOORE@saic.com> wrote:
>
>> Has anyone run Accumulo on a single server straight from memory?
>> Probably using something like a Fusion IO drive. We are trying to use it
>> without using an SSD or any spinning discs.****
>>
>> ** **
>>
>> *Matthew Moore*****
>>
>> Systems Engineer****
>>
>> SAIC, ISBU****
>>
>> Columbia, MD****
>>
>> 410-312-2542****
>>
>> ** **
>>
>
>
Re: Running Accumulo straight from Memory
Posted by William Slacum <wi...@accumulo.net>.
You could mount a RAM disk and point HDFS to it.
On Tue, Sep 11, 2012 at 9:02 AM, Moore, Matthew J. <MATTHEW.J.MOORE@saic.com
> wrote:
> Has anyone run Accumulo on a single server straight from memory? Probably
> using something like a Fusion IO drive. We are trying to use it without
> using an SSD or any spinning discs.****
>
> ** **
>
> *Matthew Moore*****
>
> Systems Engineer****
>
> SAIC, ISBU****
>
> Columbia, MD****
>
> 410-312-2542****
>
> ** **
>