On Sun, 26 Sep 2010 22:20:21 -0700 Chandra Seetharaman <sekharan@xxxxxxxxxx> 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@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
