Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Fri, Apr 15, 2016 at 1:12 PM, Michael Paquierwrote: > On Fri, Apr 15, 2016 at 12:57 PM, Fujii Masao wrote: >> On Fri, Apr 15, 2016 at 12:39 PM, Michael Paquier >> wrote: >>> On Fri, Apr 15, 2016 at 12:16 PM, Fujii Masao wrote: On Thu, Apr 14, 2016 at 8:41 PM, Michael Paquier wrote: > On Thu, Apr 14, 2016 at 5:17 PM, Masahiko Sawada > wrote: >> On Thu, Apr 14, 2016 at 1:22 PM, Michael Paquier >> wrote: >>> Yes. I'd prefer avoid a hardcoded sleep and have something that relies >>> on lookups of pg_stat_replication though, because there is no way to >>> be sure that a sleep will ever be stable on heavily loaded machines, >>> like the machines I am specialized in maintaining :) >>> It kills a bit the purpose on having checks on pg_stat_replication as >>> the validation tests are based on that, still I think that we had >>> better base those checks on a loop that has a timeout, something like >>> that in a subroutine: >>> What do you think? >> >> Look good to me. +1. +1 from me. > And so here we go... +ok($test_passed, $msg); ISTM that this change prevents the test from outputting the difference of expected and actual results when the test fails. Which would make the diagnosis of the test failure more difficult, I'm afraid. >>> >>> Well, then, it is just a matter of saving the result in a variable >>> defined out of the loop, and use is() for the test. This way, after >>> the timeout it is possible to check if the expected result and the >>> fetched result match properly or not. In other words see attached. >> >> The patch looks good to me. >> >> +my $timeout_max = 30; >> >> One comment is; isn't 30 (seconds) too large value for the timeout? >> What about just, say, 5? > > hamster can become easily quite busy to be honest. Okay, since the test would fail very rarely (I hope), probably we can live with 30 seconds timeout (it happens only when the test fails). I pushed your latest patch. Thanks! Regards, -- Fujii Masao -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Fri, Apr 15, 2016 at 12:57 PM, Fujii Masaowrote: > On Fri, Apr 15, 2016 at 12:39 PM, Michael Paquier > wrote: >> On Fri, Apr 15, 2016 at 12:16 PM, Fujii Masao wrote: >>> On Thu, Apr 14, 2016 at 8:41 PM, Michael Paquier >>> wrote: On Thu, Apr 14, 2016 at 5:17 PM, Masahiko Sawada wrote: > On Thu, Apr 14, 2016 at 1:22 PM, Michael Paquier > wrote: >> Yes. I'd prefer avoid a hardcoded sleep and have something that relies >> on lookups of pg_stat_replication though, because there is no way to >> be sure that a sleep will ever be stable on heavily loaded machines, >> like the machines I am specialized in maintaining :) >> It kills a bit the purpose on having checks on pg_stat_replication as >> the validation tests are based on that, still I think that we had >> better base those checks on a loop that has a timeout, something like >> that in a subroutine: >> What do you think? > > Look good to me. +1. >>> >>> +1 from me. >>> And so here we go... >>> >>> +ok($test_passed, $msg); >>> >>> ISTM that this change prevents the test from outputting the difference >>> of expected and actual results when the test fails. Which would make >>> the diagnosis of the test failure more difficult, I'm afraid. >> >> Well, then, it is just a matter of saving the result in a variable >> defined out of the loop, and use is() for the test. This way, after >> the timeout it is possible to check if the expected result and the >> fetched result match properly or not. In other words see attached. > > The patch looks good to me. > > +my $timeout_max = 30; > > One comment is; isn't 30 (seconds) too large value for the timeout? > What about just, say, 5? hamster can become easily quite busy to be honest. -- Michael -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Fri, Apr 15, 2016 at 12:39 PM, Michael Paquierwrote: > On Fri, Apr 15, 2016 at 12:16 PM, Fujii Masao wrote: >> On Thu, Apr 14, 2016 at 8:41 PM, Michael Paquier >> wrote: >>> On Thu, Apr 14, 2016 at 5:17 PM, Masahiko Sawada >>> wrote: On Thu, Apr 14, 2016 at 1:22 PM, Michael Paquier wrote: > Yes. I'd prefer avoid a hardcoded sleep and have something that relies > on lookups of pg_stat_replication though, because there is no way to > be sure that a sleep will ever be stable on heavily loaded machines, > like the machines I am specialized in maintaining :) > It kills a bit the purpose on having checks on pg_stat_replication as > the validation tests are based on that, still I think that we had > better base those checks on a loop that has a timeout, something like > that in a subroutine: > What do you think? Look good to me. +1. >> >> +1 from me. >> >>> And so here we go... >> >> +ok($test_passed, $msg); >> >> ISTM that this change prevents the test from outputting the difference >> of expected and actual results when the test fails. Which would make >> the diagnosis of the test failure more difficult, I'm afraid. > > Well, then, it is just a matter of saving the result in a variable > defined out of the loop, and use is() for the test. This way, after > the timeout it is possible to check if the expected result and the > fetched result match properly or not. In other words see attached. The patch looks good to me. +my $timeout_max = 30; One comment is; isn't 30 (seconds) too large value for the timeout? What about just, say, 5? Regards, -- Fujii Masao -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Fri, Apr 15, 2016 at 12:16 PM, Fujii Masaowrote: > On Thu, Apr 14, 2016 at 8:41 PM, Michael Paquier > wrote: >> On Thu, Apr 14, 2016 at 5:17 PM, Masahiko Sawada >> wrote: >>> On Thu, Apr 14, 2016 at 1:22 PM, Michael Paquier >>> wrote: Yes. I'd prefer avoid a hardcoded sleep and have something that relies on lookups of pg_stat_replication though, because there is no way to be sure that a sleep will ever be stable on heavily loaded machines, like the machines I am specialized in maintaining :) It kills a bit the purpose on having checks on pg_stat_replication as the validation tests are based on that, still I think that we had better base those checks on a loop that has a timeout, something like that in a subroutine: What do you think? >>> >>> Look good to me. +1. > > +1 from me. > >> And so here we go... > > +ok($test_passed, $msg); > > ISTM that this change prevents the test from outputting the difference > of expected and actual results when the test fails. Which would make > the diagnosis of the test failure more difficult, I'm afraid. Well, then, it is just a matter of saving the result in a variable defined out of the loop, and use is() for the test. This way, after the timeout it is possible to check if the expected result and the fetched result match properly or not. In other words see attached. -- Michael diff --git a/src/test/recovery/t/007_sync_rep.pl b/src/test/recovery/t/007_sync_rep.pl index c257b6e..d551954 100644 --- a/src/test/recovery/t/007_sync_rep.pl +++ b/src/test/recovery/t/007_sync_rep.pl @@ -22,7 +22,23 @@ sub test_sync_state $self->reload; } - my $result = $self->safe_psql('postgres', $check_sql); + my $timeout_max = 30; + my $timeout = 0; + my $result; + + # A reload may take some time to take effect on busy machines, + # hence use a loop with a timeout to give some room for the test + # to pass. + while ($timeout < $timeout_max) + { + $result = $self->safe_psql('postgres', $check_sql); + + last if ($result eq $expected); + + $timeout++; + sleep 1; + } + is($result, $expected, $msg); } -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Thu, Apr 14, 2016 at 8:41 PM, Michael Paquierwrote: > On Thu, Apr 14, 2016 at 5:17 PM, Masahiko Sawada > wrote: >> On Thu, Apr 14, 2016 at 1:22 PM, Michael Paquier >> wrote: >>> Yes. I'd prefer avoid a hardcoded sleep and have something that relies >>> on lookups of pg_stat_replication though, because there is no way to >>> be sure that a sleep will ever be stable on heavily loaded machines, >>> like the machines I am specialized in maintaining :) >>> It kills a bit the purpose on having checks on pg_stat_replication as >>> the validation tests are based on that, still I think that we had >>> better base those checks on a loop that has a timeout, something like >>> that in a subroutine: >>> What do you think? >> >> Look good to me. +1. +1 from me. > And so here we go... +ok($test_passed, $msg); ISTM that this change prevents the test from outputting the difference of expected and actual results when the test fails. Which would make the diagnosis of the test failure more difficult, I'm afraid. Regards, -- Fujii Masao -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Thu, Apr 14, 2016 at 5:17 PM, Masahiko Sawadawrote: > On Thu, Apr 14, 2016 at 1:22 PM, Michael Paquier > wrote: >> Yes. I'd prefer avoid a hardcoded sleep and have something that relies >> on lookups of pg_stat_replication though, because there is no way to >> be sure that a sleep will ever be stable on heavily loaded machines, >> like the machines I am specialized in maintaining :) >> It kills a bit the purpose on having checks on pg_stat_replication as >> the validation tests are based on that, still I think that we had >> better base those checks on a loop that has a timeout, something like >> that in a subroutine: >> What do you think? > > Look good to me. +1. And so here we go... -- Michael diff --git a/src/test/recovery/t/007_sync_rep.pl b/src/test/recovery/t/007_sync_rep.pl index c257b6e..908fe49 100644 --- a/src/test/recovery/t/007_sync_rep.pl +++ b/src/test/recovery/t/007_sync_rep.pl @@ -22,8 +22,28 @@ sub test_sync_state $self->reload; } - my $result = $self->safe_psql('postgres', $check_sql); - is($result, $expected, $msg); + my $timeout_max = 30; + my $timeout = 0; + my $test_passed = 0; + + # A reload may take some time to take effect on busy machines, + # hence use a loop with a timeout to give some room for the test + # to pass. + while ($timeout < $timeout_max) + { + my $result = $self->safe_psql('postgres', $check_sql); + + if ($result eq $expected) + { + $test_passed = 1; + last; + } + + $timeout++; + sleep 1; + } + + ok($test_passed, $msg); } # Initialize master node -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Thu, Apr 14, 2016 at 1:22 PM, Michael Paquierwrote: > On Thu, Apr 14, 2016 at 11:29 AM, Fujii Masao wrote: >> On Wed, Apr 13, 2016 at 4:54 PM, Michael Paquier >> wrote: >>> On Fri, Apr 8, 2016 at 4:49 PM, Fujii Masao wrote: Add regression tests for multiple synchronous standbys. Authors: Suraj Kharage, Michael Paquier, Masahiko Sawada, refactored by me Reviewed-By: Kyotaro Horiguchi >>> >>> Well, we are not quite there yet: >>> http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=hamster=2016-04-12%2016%3A00%3A06 >>> >>> # Running: pg_ctl -D >>> /home/buildfarm/data/buildroot/HEAD/pgsql.build/src/test/recovery/tmp_check/data_master_Qmuz/pgdata >>> reload >>> server signaled >>> not ok 2 - asterisk in synchronous_standby_names >>> >>> # Failed test 'asterisk in synchronous_standby_names' >>> # at t/007_sync_rep.pl line 26. >>> # got: 'standby1|1|sync >>> # standby2|1|potential >>> # standby3|0|async' >>> # expected: 'standby1|1|sync >>> # standby2|1|potential >>> # standby3|1|potential' >> >> This seems to be a timing issue. >> >> There can be small window after SIGHUP is sent before walsender updates >> its priority based on new s_s_names. If pg_stat_replication is checked >> before that update, it displays unexpected output. Probably we need to >> sleep a few second after pg_ctl reload before pg_stat_replication. > > Yes. I'd prefer avoid a hardcoded sleep and have something that relies > on lookups of pg_stat_replication though, because there is no way to > be sure that a sleep will ever be stable on heavily loaded machines, > like the machines I am specialized in maintaining :) > It kills a bit the purpose on having checks on pg_stat_replication as > the validation tests are based on that, still I think that we had > better base those checks on a loop that has a timeout, something like > that in a subroutine: > test_passed = 0; > while ($timeout < 30) > { > $result = $node->psql('SELECT blah FROM pg_stat_replication'); > if ($result eq $expected) > { > test_passed = 1; > break; > } > sleep 1; > $timeout++; > } > ok($test_passed, $test_name); > > What do you think? Look good to me. +1. Regards, -- Masahiko Sawada -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Thu, Apr 14, 2016 at 11:29 AM, Fujii Masaowrote: > On Wed, Apr 13, 2016 at 4:54 PM, Michael Paquier > wrote: >> On Fri, Apr 8, 2016 at 4:49 PM, Fujii Masao wrote: >>> Add regression tests for multiple synchronous standbys. >>> >>> Authors: Suraj Kharage, Michael Paquier, Masahiko Sawada, refactored by me >>> Reviewed-By: Kyotaro Horiguchi >> >> Well, we are not quite there yet: >> http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=hamster=2016-04-12%2016%3A00%3A06 >> >> # Running: pg_ctl -D >> /home/buildfarm/data/buildroot/HEAD/pgsql.build/src/test/recovery/tmp_check/data_master_Qmuz/pgdata >> reload >> server signaled >> not ok 2 - asterisk in synchronous_standby_names >> >> # Failed test 'asterisk in synchronous_standby_names' >> # at t/007_sync_rep.pl line 26. >> # got: 'standby1|1|sync >> # standby2|1|potential >> # standby3|0|async' >> # expected: 'standby1|1|sync >> # standby2|1|potential >> # standby3|1|potential' > > This seems to be a timing issue. > > There can be small window after SIGHUP is sent before walsender updates > its priority based on new s_s_names. If pg_stat_replication is checked > before that update, it displays unexpected output. Probably we need to > sleep a few second after pg_ctl reload before pg_stat_replication. Yes. I'd prefer avoid a hardcoded sleep and have something that relies on lookups of pg_stat_replication though, because there is no way to be sure that a sleep will ever be stable on heavily loaded machines, like the machines I am specialized in maintaining :) It kills a bit the purpose on having checks on pg_stat_replication as the validation tests are based on that, still I think that we had better base those checks on a loop that has a timeout, something like that in a subroutine: test_passed = 0; while ($timeout < 30) { $result = $node->psql('SELECT blah FROM pg_stat_replication'); if ($result eq $expected) { test_passed = 1; break; } sleep 1; $timeout++; } ok($test_passed, $test_name); What do you think? -- Michael -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Wed, Apr 13, 2016 at 4:54 PM, Michael Paquierwrote: > On Fri, Apr 8, 2016 at 4:49 PM, Fujii Masao wrote: >> Add regression tests for multiple synchronous standbys. >> >> Authors: Suraj Kharage, Michael Paquier, Masahiko Sawada, refactored by me >> Reviewed-By: Kyotaro Horiguchi > > Well, we are not quite there yet: > http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=hamster=2016-04-12%2016%3A00%3A06 > > # Running: pg_ctl -D > /home/buildfarm/data/buildroot/HEAD/pgsql.build/src/test/recovery/tmp_check/data_master_Qmuz/pgdata > reload > server signaled > not ok 2 - asterisk in synchronous_standby_names > > # Failed test 'asterisk in synchronous_standby_names' > # at t/007_sync_rep.pl line 26. > # got: 'standby1|1|sync > # standby2|1|potential > # standby3|0|async' > # expected: 'standby1|1|sync > # standby2|1|potential > # standby3|1|potential' This seems to be a timing issue. There can be small window after SIGHUP is sent before walsender updates its priority based on new s_s_names. If pg_stat_replication is checked before that update, it displays unexpected output. Probably we need to sleep a few second after pg_ctl reload before pg_stat_replication. Regards, -- Fujii Masao -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] [COMMITTERS] pgsql: Add regression tests for multiple synchronous standbys.
On Fri, Apr 8, 2016 at 4:49 PM, Fujii Masaowrote: > Add regression tests for multiple synchronous standbys. > > Authors: Suraj Kharage, Michael Paquier, Masahiko Sawada, refactored by me > Reviewed-By: Kyotaro Horiguchi Well, we are not quite there yet: http://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=hamster=2016-04-12%2016%3A00%3A06 # Running: pg_ctl -D /home/buildfarm/data/buildroot/HEAD/pgsql.build/src/test/recovery/tmp_check/data_master_Qmuz/pgdata reload server signaled not ok 2 - asterisk in synchronous_standby_names # Failed test 'asterisk in synchronous_standby_names' # at t/007_sync_rep.pl line 26. # got: 'standby1|1|sync # standby2|1|potential # standby3|0|async' # expected: 'standby1|1|sync # standby2|1|potential # standby3|1|potential' I am adding an open item for now, I guess that's on my plate, as co-authorm and one who has the environment to trigger that (didn't see it 10 times in a row in my tests though). -- Michael -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers