Re: [Gluster-devel] Scaled down a bit.

[Chris Johnson]

On Wed, 28 Nov 2007, Kevan Benson wrote:

     Ok, better.  Does work on the client side though.  Doesn't seem
to be to great on the server side for some reason.

     I just tried my simple test with readahead on the cl;ient side.
No difference.  Here's what I used.

volume readahead
  type performance/read-ahead
  option page-size 128kb ### in bytes
  option page-count 2 ### memory cache size is page-count x page-size per file
  subvolumes client
end-volume
~ 
Maybe the page size or count needs to be bigger?

> Krishna Srinivas wrote:
> > On Nov 28, 2007 11:11 PM, Chris Johnson <address@hidden> 
> > wrote:
> > > On Wed, 28 Nov 2007, Kevan Benson wrote:
> > > > Chris Johnson wrote:
> > > > >      I also tried the io-cache on the client side.  MAN does that
> > > > > work.  I had a 256 MB cache defind.  A reread of my 24 MB file took 72
> > > > > MS.  I don't think it even bothered with the server much.  I need to
> > > > > try that on the server.  Might help if a bunch of computer nodes
> > > > > hammer on the same file at the same time.
> > > > Careful with io-cache and io-threads together, depending on where you 
> > > > define
> > > > it (I think), the cache is per-thread.  so if you have 8 threads and a 
> > > > 256 MB
> > > > cache defined, be prepared for 2 GB of cache use...
> >
> > No, If you define one io-cache translator there is only one cache. All the
> > threads will refer to the same io-cache translator with which it is 
> > associated
>
> Ah.  Is this newer?  I thought I tried this a few months ago and saw a lot of 
> memory usage.  Maybe I just ASSumed. ;)
>
> --
>
> -Kevan Benson
> -A-1 Networks

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