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Accumulo >> mail # user >> Running Accumulo straight from Memory

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Re: Running Accumulo straight from Memory


  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" <[EMAIL PROTECTED]>
Sent: Wednesday, September 12, 2012 12:32:31 PM
Subject: RE: Running Accumulo straight from Memory

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.




From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Adam Fuchs
Sent: Tuesday, September 11, 2012 5:30 PM
Subject: Re: Running Accumulo straight from Memory


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?

On Tue, Sep 11, 2012 at 12:02 PM, Moore, Matthew J. < [EMAIL PROTECTED] > 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


Columbia, MD