Varnish 2.0.6 nuking all my objects?

[Barry Abrahamson]

On Feb 25, 2010, at 12:47 PM, David Birdsong wrote:

> On Thu, Feb 25, 2010 at 8:41 AM, Barry Abrahamson <barry at automattic.com> wrote:
>> 
>> On Feb 25, 2010, at 2:26 AM, David Birdsong wrote:
>> 
>>> I have seen this happen.
>>> 
>>> I have a similar hardware setup, though I changed the multi-ssd raid
>>> into 3 separate cache file arguments.
>> 
>> Did you try RAID and switch to the separate cache files because performance was better?
> seemingly so.
> 
> for some reason enabling block_dump showed that kswapd was always
> writing to those devices despite their not being any swap space on
> them.
> 
> i searched around fruitlessly to try to understand the overhead of
> software raid to explain this, but once i discovered varnish could
> take on multiple cache files, i saw no reason for the software raid
> and just abandoned it.

Interesting - I will try it out!  Thanks for the info.


>>> We had roughly 240GB storage space total, after about 2-3 weeks and
>>> sm_bfree reached ~20GB. lru_nuked started incrementing, sm_bfree
>>> climbed to ~60GB, but lru_nuking never stopped.
>> 
>> How did you fix it?
> i haven't yet.
> 
> i'm changing up how i cache content, such that lru_nuking can be
> better tolerated.

In my case, Varnish took a cache of 1 million objects, purged 920k of them.  When there were 80k objects left the child restarted, thus dumping the remaining 80k :)  


--
Barry Abrahamson | Systems Wrangler | Automattic
Blog: http://barry.wordpress.com