Re: 2.4.20pre5aa2

[Samuel Flory <sflory@rackable.com>]

Stephen Lord wrote:

>On Thu, 2002-09-12 at 19:23, Andrea Arcangeli wrote:
>  
>
>>that seems a bug in xfs, it BUG() if vmap fails, it must not BUG(), it
>>must return -ENOMEM to userspace instead, or it can try to recollect and
>>release some of the other vmalloced entries. Most probably you run into
>>an address space shortage, not a real ram shortage, so to workaround it
>>you can recompile with CONFIG_2G and it'll probably work, also dropping
>>the gap page in vmalloc may help workaround it (there's no config option
>>for it though). It could be also a vmap leak, maybe a missing vfree,
>>just some idea.
>>
>>    
>>
>
>We hold vmalloced space for very short periods of time, in fact
>filesystem recovery and large extended attributes are the only
>cases. In this case we should be attempting to remap 2 pages
>together. The only way out of this would be to fail the whole
>mount at this point. I suspect a leak elsewhere.
>
>Samuel, when you mounted xfs and it oopsed, was it shortly after bootup?
>

  Yes I'd just logged in and manually mounted it.

>Also, how far did your dbench run get before it hung? I tried the
>kernel, but I paniced during startup - then I realized I did not 
>apply the patch to fix the xfs/scheduler interactions first.
>  
>
It looked around 1/4 to 1/2 done with dbench 32.  I'm not sure if it was 
the 1st or second run.  I run dbench from a script:
sync
sync
./dbench 2
sync
sync
./dbench 4
sync
sync
./dbench 8
sync
sync
./dbench 16
sync
sync
./dbench 32
sync
sync
./dbench 64
sync
sync
<repeats >

  I generally use this script narrow down which configurations seem to 
be most promising.

>How much memory is in the machine by the way? 
>
4G ram, and 4G swap.