[stgt] [PATCH 00/12] Fix Thread per target feature
fujita.tomonori at lab.ntt.co.jp
Mon Sep 27 08:24:41 CEST 2010
On Sun, 26 Sep 2010 22:20:21 -0700
Chandra Seetharaman <sekharan at us.ibm.com> wrote:
> Hello All,
> I started looking at the thread per target issue recently since Tomo
> pulled it off for stability issues. When I started looking at it, Tomo
> suggested that the problem could most likely be in the context of
> disconnects. I started with that suggestion.
> I started testing the feature with dbench's iscsi feature. I used 20
> targets built on ramdisk file system and used 50 initiators from dbench. I
> made the tests run for 5 seconds per iteration. Basically 50 initators
> connecting to 20 targets each, run tests for 5 seconds and disconnect,
> the same thing iterates forever (or till it dies :).
> When I started the tests with the code that was pulled off, tgtd would
> segfault and die in 3-5 minutes. Debugging more and more, I found most
> of the issues were race.
> Mainly, I found 3 issues,
> - tgt_events_list (global) needed protection
> - it_nexus_list (in struct target) needed protection
> - setting of tcp_conn->pthread to 1 in iscsi_tcp_conn_nexus_init()
> need to happen before do_tgt_event_add().
> In the process of understanding the patch and locating the issue, I ended
> up splitting Tomo's original patches into multiple small patches by
> separting the patches to incorporate simple changes each, and now have a net
> of 12 patches :)
> IOW, these set of patches are same as Tomo's original 3 patches except the
> main 3 changes mentioned above :), (Note that there may be some simple
> fixes too).
> This set of patches with 1.0.8 ran the same dbench tests for over 24 hours.
Sounds promising! Thanks a lot!
I am at Linux.con Japan conference until Wed so probably I can't
review this for a while. But I'll review this after that.
Can anyone test the patchset meanwhile?
btw, the first patch can't be applied to the current git cleanly. The
second patch can't too.
To unsubscribe from this list: send the line "unsubscribe stgt" in
the body of a message to majordomo at vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
More information about the stgt