Since the replication protocol deals with TimestampTz, we need to
care for the floating point case as well in the frontend tools.
Fujii Masao, with changes from Magnus Hagander
When backing up from a standby server, the backup process
will not automatically switch xlog segment. So we must
accept a partially transferred xlog file in this case, but
rename it into position anyway.
In passing, merge the two callbacks for segment end and
stop stream into a single callback, since their implementations
were close to identical, and rename this callback to
reflect that it stops streaming rather than continues it.
Patch by Magnus Hagander, review by Fujii Masao
Teach pg_basebackup in streaming mode to deal with keepalive messages.
Also change the order of checks to complain at the message rather than
block size when a new message is introduced.
In passing, switch to using sizeof() instead of hardcoded sizes for
WAL protocol structs.
Instead of filling files as they appear, pre-pad the
WAL files received when streaming xlog the same way
that the server does. Data is streamed into a .partial
file which is then renamed()d into palce when it's complete,
but it will always be 16MB.
This also means that the starting position for pg_receivexlog
is now simply right after the last complete segment, and we
never need to deal with partial segments there.
Patch by me, review by Fujii Masao
Add option for parallel streaming of the transaction log while a
base backup is running, to get the logfiles before the server has
removed them.
Also add a tool called pg_receivexlog, which streams the transaction
log into files, creating a log archive without having to wait for
segments to complete, thus decreasing the window of data loss without
having to waste space using archive_timeout. This works best in
combination with archive_command - suggested usage docs etc coming later.
