On Fri, Jun 13, 2014 at 4:48 PM, Heikki Linnakangas <hlinnakan...@vmware.com> wrote: > On 06/13/2014 10:14 AM, Michael Paquier wrote: >> >> On Mon, Jun 2, 2014 at 9:55 PM, Michael Paquier >> <michael.paqu...@gmail.com> wrote: >>> >>> On Wed, Apr 23, 2014 at 9:43 PM, Heikki Linnakangas >>> <hlinnakan...@vmware.com> wrote: >>> Perhaps there are parts of what is proposed here that could be made >>> more generalized, like the masking functions. So do not hesitate if >>> you have any opinion on the matter. >> >> OK, attached is the result of this hacking: >> >> Buffer capture facility: check WAL replay consistency >> >> It is a tool aimed to be used by developers and buildfarm machines >> that can be used to check for consistency at page level when replaying >> WAL files among several nodes of a cluster (generally master and >> standby node). >> >> This facility is made of two parts: >> - A server part, where all the changes happening at page level are >> captured and inserted in a file called buffer_captures located at the >> root of PGDATA. Each buffer entry is masked to make the comparison >> across node consistent (flags like hint bits for example) and then >> each buffer is captured is with the following format as a single line >> of the output file: >> LSN: %08X/%08X page: PAGE_IN_HEXA >> Hexadecimal format makes it easier to detect differences between >> pages, and format is chosen to facilitate comparison between buffer >> entries. >> - A client part, located in contrib/buffer_capture_cmp, that can be >> used to compare buffer captures between nodes. > > > Oh, you moved the masking code from the client tool to the backend. Why? > When debugging, it's useful to have the genuine, non-masked page image > available. My thought is to share the CPU effort of masking between backends... That's not a big deal to move them back to the client tool 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
