Hi I have reverted to cp as archive command, but know under heavy load (> 150 WAL segments in a minute) it happens that some wal segments gets corrupted:
German Becker wrote: > Here is the archive part of the config: > > archive_mode = on # allows archiving to be done > # (change requires restart) > archive_command = '/var/lib/postgresql/scripts/archive_copy.sh %p %f' # command to use to > archive a logfile segment > #archive_timeout = 0 # force a logfile segment switch after this > # number of seconds; 0 disables
So the problem might be in that script.
> The archive coommand makes a local copy and then it copies to the backup server via ssh. Both copies > are md5-checked and retried up to 3 times in case of failure.
archive_command should not retry the operation, but rather return a non-zero return code.
> I have seen under heavy load that some WALs are skipped, some have less size, some are corrupted (i,e, > the loop fails 3 times). > I'm not sure about the return value (checking it). What is the expected behaviour of the archiver? > Will it retry de archive if archive command returns differnt than 0? Will it retain the WAL segment > until it is succesfuly archived?
archive_command should exit with zero only if the WAL segment was archived successfully. PostgreSQL will retry and retain the WAL segment until archival succeeds.