[Gluster-users] Performance Issue with Webserver

[Vikas Gorur]

On May 4, 2010, at 10:31 AM, Jenn Fountain wrote:
> 
> #volume writebehind
> #    type performance/write-behind
> #    option cache-size 4MB
> #    subvolumes mirror-0
> #end-volume
> 
> volume readahead
>    type performance/read-ahead
>    option page-count 4
>    subvolumes mirror-0
>    #subvolumes writebehind
> end-volume
> 
> volume iocache
>    type performance/io-cache
>    option cache-size 1GB
>    option cache-timeout 1
>    subvolumes readahead
> end-volume
> 
> volume quickread
>    type performance/quick-read
>    option cache-timeout 1
>    option max-file-size 64kB
>    subvolumes iocache
> end-volume
> 
> volume statprefetch
>    type performance/stat-prefetch
>    subvolumes quickread
> end-volume
> 
> volume iothreads
>    type performance/io-threads
>    option thread-count 16
>    subvolumes statprefetch
> end-volume
> 
> If you need any other information, let me know. Thank you in advance.

The configuration is not really optimal. I would advise you to:

- remove io-threads (io-threads is only really needed on the server).
- remove read-ahead, it won't help in this case.
- increase the cache-timeout to a higher value for quick-read, since you are doing only reads.

Please tell us the numbers you get after making these changes. You should also do atleast a few thousand requests to smooth out random fluctuations. Comparing the times for a single request does not tell us much.

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Vikas Gorur
Engineer - Gluster, Inc.
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