[Gluster-devel] Excessive memory usage with 1.3.12

[Krishna Srinivas]

Dan, Lukas, Thomas,

Internally io-cache limits the cache size to 120% of what is
configured in the spec file. If you say 2GB, memory usage can go up to
2.4-2.5 GB. This is creating confusion, we will make the necessary
change. Can you guys check if the memory usage goes beyond the 120%
limit and keeps increasing?

Dan, can you see if the memory usage can go to 3GB? It will be easier
for you to configure cache-size as 512MB and see if glusterfs usage
grows to 1GB.

Thanks
Krishna

On Sat, Nov 8, 2008 at 1:12 AM, Dan Parsons <dparsons at nyip.net> wrote:
> To be fair, I'm not even sure it's technically a "leak", it's just io-cache
> not limiting itself to the cache-size setting. As in, io-cache is doing its
> job, it's just doing it a bit .. too enthusiastically.
>
> First, here's my io-cache block:
>
> volume ioc
>  type performance/io-cache
>  subvolumes stripe0         # In this example it is 'client' you may have to
> change it according to your spec file.
>  option page-size 1MB      # 128KB is default
>  option cache-size 2048MB    # 32MB is default
>  option force-revalidate-timeout 5 # 1second is default
>  option priority *.psiblast:3,*.seq:2,*:1
> end-volume
>
> And for my test:
>
> [root at cpu26 ~]# cd /distfs
> [root at cpu26 distfs]# ls -lah bigfile.img
> -rw-r--r-- 1 root employees 6.3G Aug 26 00:21 bigfile.img
>
> Note the memory usage of a freshly started glusterfs client:
> root     23972  0.0  0.0 110340  1540 ?        Ssl  11:37   0:00 [glusterfs]
>
> Now I do this:
> [root at cpu26 distfs]# cat bigfile.img > /dev/null
>
> The glusterfs memory footprint grows at a nice rate. In just a few seconds
> it's gone from 110kb to 2.5GB, way past my cache-size limit.
>
> root     23972  9.4 61.8 2590552 2503164 ?     Ssl  11:37   0:14 [glusterfs]
>
> This box has only 4GB RAM so i killed the 'cat' process before things got
> out of hand. But, there's your test.
>
> [root at cpu26 ~]# glusterfs --version
> glusterfs 1.3.11 built on Aug 21 2008 11:26:38
> Repository revision: glusterfs--mainline--2.5--patch-795
>
>
> Dan Parsons
>
>
> On Nov 7, 2008, at 11:31 AM, Krishna Srinivas wrote:
>
>> Lukas, Dan,
>>
>> Are you sure that its a leak of io-cache? did you try by removing the
>> translator and not observe the leak?
>>
>> What made you conclude that cache-size option was being ignored? It
>> could be a memory leak by io-cache at some other place too.
>>
>> I tried to make io-cache memleak, but its not happening, what
>> operations do you guys do to see the leak? can you see if some simple
>> test case makes it leak? (so that it will be easy for me to reproduce
>> the bug here and fix it)
>>
>> Thanks!
>> Krishna
>>
>> On