Re: [squid-users] endless growing swap.state after reboot

From: Tek Bahadur Limbu <teklimbu@dont-contact.us>
Date: Wed, 8 Aug 2007 16:38:39 +0545

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On Wed, 8 Aug 2007 07:12:37 -0300 (BRT)
"Michel Santos" <michel@lucenet.com.br> wrote:

>
> I am coming back with this issue again since it is still persistent
>
> This problem is real and easy to repeat and destroys the complete
> cache_dir content. The squid vesion is 2.6-Stable14 and certainly it is
> with all 2.6 versions I tested so far. This problem is not as easy to
> launch with 2.5 where it happens in a different way after an unclean
> shutdown.
>
> How to repeat this is easy, on any 2.6 version you shut down the machine
> with rc.shutdown time shorter than squid needs to close the cache_dirs
> what then kills the still open squid process[es] - no hard reset or power
> failure is necessary.
>
> After reboot squid gets crazy with swap.state on the affected cache-dirs
> as you can see in messages and cache_dir graphs I put together from two
> different machines in the following file
>
> Important here, the partitions ARE clean from OS's view and fsck is not
> beeing invoked and running fsck manually before mounting them does NOT
> change anything.
>
> You also can see on the machine with 4 cache_dirs that only two dirs are
> beeing destroyd, probably because of their size which needed longer to
> close them
>
> http://suporte.lucenet.com.br/supfiles/cache-prob.tar.gz
>
> This happens with 100% sure hit with AUFS and DISKD and UFS still does
> what squid-2.5 did:
>
>
> - squid-2.6 creates a never-ending-growing swap.state until the disk is
> full and the squid process dies becaus of disk full
>
> - squid-2.5 let the swap.state as is and empties the cache_dirs partially
> or completely
>
>
> Even I can see that this can be understood as unclean shutdown I must
> insist that the growing swap.state and cache_dir Store rebuild negative
> values and it's 2000%-and-what-ever values in messages are kind of strange
> and probably wrong
>
> What I do not understand here is the following.
>
> So fare I ever was told that the problem is a corrupted swap.state file
>
> But for my understandings the cached file is beeing referenced in
> swap.state soon it is cached.
>
> This obviously should have been happened BEFORE squid is shutting down or
> dies so why squid still needs to write to swap.state at this stage?
>
> And if it for any reason did not happened than the swap.state rebuild
> process detect and destroys the invalid objects in each cache_dir on
> startup
>
> If squid needs to read swap.state in order to close the cache_dirs than it
> would be enough to have swap.state open for reading? Then certainly it
> does not get corrupted or not?
>
>
> Since you tell me that *nobody* has this problem what I certainly can not
> believe ;) but seems you guys are using linux or windows then might this
> be related to freebsd's softupdate on the file system and squid can not
> handle this? Should I disable it and check it out?

I agree with Michel. I get this problem in my FreeBSD 2.6 squid boxes from time to time.
I usually have to delete the cache_dirs and re-create them to resolve this issue.
But still, this takes some time and resources.

I guess that I am lucky that this does not arise frequently.

Thanking you...

>
>
> michel
> ...
>
>
>
>
> ****************************************************
> Datacenter Matik http://datacenter.matik.com.br
> E-Mail e Data Hosting Service para Profissionais.
> ****************************************************
>
>

- --

With best regards and good wishes,

Yours sincerely,

Tek Bahadur Limbu

(TAG/TDG Group)
Jwl Systems Department

Worldlink Communications Pvt. Ltd.

Jawalakhel, Nepal
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Received on Wed Aug 08 2007 - 04:53:36 MDT

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