[OpenAFS] freezes acessing /afs/.git

Markus Köberl spsc-sysadmin@mlist.tugraz.at
Sun, 10 Aug 2014 08:18:25 +0200


On Sunday 10 August 2014 0:31:14 Troy Benjegerdes wrote:
> This really needs some sort of testcase and regression tests. 
> 
> I keep randomly hitting this stuff and I just 'got used to' my machine 
> (or maybe just a process) become unusable for awhile. It's the kind of
> thing that someone tries AFS, and runs into this, and then never uses
> it again.

Yes and things are changing over years so that you never know the real problem. For our cell -afsdb got used since the beginning. But it got much worse after the debian upgrade to wheeze. At the end all users where affected. With squeeze it was only noticeable on kde. It may also correlate with changes on our name server, I do not know about this as it gets managed central.

> Part of the problem is also applications that look for random files all
> over the place
> 
> I think negative caching and maybe some sort of 'cell-configured' negative
> cache file is going to be necessary.

Yes I think this will maybe solve the problem for a lot of programs. But there are also things like the bash auto-completion which also get affected by the timeouts where caching maybe wont work that good. But in this case particular case people learn what they should not use the tab key in the /afs directory.

In my home network I tested a lot of settings but never got negative caching with bind working probably. I observe always about 1.3s for searches which should be cached. At work it was faster.


During the weekend I disabled -afsdb at work on all hosts. I am curios about the feedback...