nudge, nudge
On Wed, Jan 05, 2011 at 02:05:55PM +0100, Dejan Muhamedagic wrote: > On Tue, Jan 04, 2011 at 01:53:00PM -0700, Steven Dake wrote: > > On 12/23/2010 06:14 AM, Dejan Muhamedagic wrote: > > > Hi, > > > > > > On Wed, Dec 01, 2010 at 05:30:44PM +0200, Vladislav Bogdanov wrote: > > >> 01.12.2010 16:32, Dejan Muhamedagic wrote: > > >>> Hi, > > >>> > > >>> On Tue, Nov 23, 2010 at 12:53:42PM +0200, Vladislav Bogdanov wrote: > > >>>> Hi Steven, hi all. > > >>>> > > >>>> I often see this assert on one of nodes after I stop corosync on some > > >>>> another node in newly-setup 4-node cluster. > > >>> > > >>> Does the assert happen on a node lost event? Or once new > > >>> partition is formed? > > >> > > >> I first noticed it when I rebooted another node, just after console said > > >> that OpenAIS is stopped. > > >> > > >> Can't say right now, what exactly event did it follow, I'm actually > > >> fighting with several problems with corosync, pacemaker, NFS4 and > > >> phantom uncorrectable ECC errors simultaneously and I'm a bit lost with > > >> all of them. > > >> > > >>> > > >>>> #0 0x00007f51953e49a5 in raise () from /lib64/libc.so.6 > > >>>> #1 0x00007f51953e6185 in abort () from /lib64/libc.so.6 > > >>>> #2 0x00007f51953dd935 in __assert_fail () from /lib64/libc.so.6 > > >>>> #3 0x00007f5196176406 in memb_consensus_agreed > > >>>> (instance=0x7f5196554010) at totemsrp.c:1194 > > >>>> #4 0x00007f519617b2f3 in memb_join_process (instance=0x7f5196554010, > > >>>> memb_join=0x262f628) at totemsrp.c:3918 > > >>>> #5 0x00007f519617b619 in message_handler_memb_join > > >>>> (instance=0x7f5196554010, msg=<value optimized out>, msg_len=<value > > >>>> optimized out>, endian_conversion_needed=<value optimized out>) > > >>>> at totemsrp.c:4161 > > >>>> #6 0x00007f5196173ba7 in passive_mcast_recv (rrp_instance=0x2603030, > > >>>> iface_no=0, context=<value optimized out>, msg=<value optimized out>, > > >>>> msg_len=<value optimized out>) at totemrrp.c:720 > > >>>> #7 0x00007f5196172b44 in rrp_deliver_fn (context=<value optimized > > >>>> out>, > > >>>> msg=0x262f628, msg_len=420) at totemrrp.c:1404 > > >>>> #8 0x00007f5196171a76 in net_deliver_fn (handle=<value optimized out>, > > >>>> fd=<value optimized out>, revents=<value optimized out>, > > >>>> data=0x262ef80) > > >>>> at totemudp.c:1244 > > >>>> #9 0x00007f519616d7f2 in poll_run (handle=4858364909567606784) at > > >>>> coropoll.c:510 > > >>>> #10 0x0000000000406add in main (argc=<value optimized out>, argv=<value > > >>>> optimized out>, envp=<value optimized out>) at main.c:1680 > > >>>> > > >>>> Last fplay lines are: > > >>>> > > >>>> rec=[36124] Log Message=Delivering MCAST message with seq 1366 to > > >>>> pending delivery queue > > >>>> rec=[36125] Log Message=Delivering MCAST message with seq 1367 to > > >>>> pending delivery queue > > >>>> rec=[36126] Log Message=Received ringid(10.5.4.52:12660) seq 1366 > > >>>> rec=[36127] Log Message=Received ringid(10.5.4.52:12660) seq 1367 > > >>>> rec=[36128] Log Message=Received ringid(10.5.4.52:12660) seq 1366 > > >>>> rec=[36129] Log Message=Received ringid(10.5.4.52:12660) seq 1367 > > >>>> rec=[36130] Log Message=releasing messages up to and including 1367 > > >>>> rec=[36131] Log Message=FAILED TO RECEIVE > > >>>> rec=[36132] Log Message=entering GATHER state from 6. > > >>>> rec=[36133] Log Message=entering GATHER state from 0. > > >>>> Finishing replay: records found [33993] > > >>>> > > >>>> What could be the reason for this? Bug, switches, memory errors? > > >>> > > >>> The assertion fails because corosync finds out that > > >>> instance->my_proc_list and instance->my_failed_list are > > >>> equal. That happens immediately after the "FAILED TO RECEIVE" > > >>> message which is issued when fail_recv_const token rotations > > >>> happened without any multicast packet received (defaults to 50). > > > > > > I took a look at the code and the protocol specification again > > > and it seems like that assert is not valid since Steve patched > > > the part dealing with the "FAILED TO RECEIVE" condition. The > > > patch is from 2010-06-03 posted to the list here > > > http://marc.info/?l=openais&m=127559807608484&w=2 > > > > > > The last hunk of the patch contains this code (exec/totemsrp.c): > > > > > > 3933 if (memb_consensus_agreed (instance) && > > > instance->failed_to_recv == 1) { > > > 3934 instance->failed_to_recv = 0; > > > 3935 srp_addr_copy (&instance->my_proc_list[0], > > > 3936 &instance->my_id); > > > 3937 instance->my_proc_list_entries = 1; > > > 3938 instance->my_failed_list_entries = 0; > > > 3939 > > > 3940 memb_state_commit_token_create (instance); > > > 3941 > > > 3942 memb_state_commit_enter (instance); > > > 3943 return; > > > 3944 } > > > > > > This code never got a chance to run because on failed_to_recv > > > the two sets (my_process_list and my_failed_list) are equal which > > > makes the assert fail in memb_consensus_agreed(): > > > > > > 1185 memb_set_subtract (token_memb, &token_memb_entries, > > > 1186 instance->my_proc_list, instance->my_proc_list_entries, > > > 1187 instance->my_failed_list, instance->my_failed_list_entries); > > > ... > > > 1195 assert (token_memb_entries >= 1); > > > > > > In other words, it's something like this: > > > > > > if A: > > > if memb_consensus_agreed() and failed_to_recv: > > > form a single node ring and try to recover > > > > > > memb_consensus_agreed(): > > > assert(!A) > > > > > > Steve, can you take a look and confirm that this holds. > > > > > > Cheers, > > > > > > > Dejan, > > > > sorry for delay in response - big backlog which is mostly cleared out :) > > No problem. > > > The assert definitely isn't correct, but removing it without addressing > > the contents of the proc and fail lists is also not right. That would > > cause the logic in the if statement at line 3933 not to be executed > > (because the first part of the if would evaluate to false) > > Actually it wouldn't. The agreed variable is set to 1 and it > is going to be returned unchanged. > > > I believe > > what we should do is check the "failed_to_recv" value in > > memb_consensus_agreed instead of at line 3933. > > > > The issue with this is memb_state_consensus_timeout_expired which also > > executes some 'then' logic where we may not want to execute the > > failed_to_recv logic. > > Perhaps we should just > > 3933 if (instance->failed_to_recv == 1) { > > ? In case failed_to_recv both proc and fail lists are equal so > checking for memb_consensus_agreed won't make sense, right? > > > If anyone has a reliable reproducer and can forward to me, I'll test out > > a change to address this problem. Really hesitant to change anything in > > totemsrp without a test case for this problem - its almost perfect ;-) > > Since the tester upgraded the switch firmware they couldn't > reproduce it anymore. > > Would compiling with these help? > > /* > * These can be used to test the error recovery algorithms > * #define TEST_DROP_ORF_TOKEN_PERCENTAGE 30 > * #define TEST_DROP_COMMIT_TOKEN_PERCENTAGE 30 > * #define TEST_DROP_MCAST_PERCENTAGE 50 > * #define TEST_RECOVERY_MSG_COUNT 300 > */ > > Cheers, > > Dejan > > > Regards > > -steve > > > > > Dejan > > > _______________________________________________ > > > Openais mailing list > > > [email protected] > > > https://lists.linux-foundation.org/mailman/listinfo/openais > > > > _______________________________________________ > > Openais mailing list > > [email protected] > > https://lists.linux-foundation.org/mailman/listinfo/openais > _______________________________________________ > Openais mailing list > [email protected] > https://lists.linux-foundation.org/mailman/listinfo/openais _______________________________________________ Openais mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/openais
