22 Commits (f116b1f5b8d36e54404b36f1aba1295cbcfc4fdc)

Author	SHA1	Message	Date
Bruce Momjian	6416a82a62	Remove unnecessary #include references, per pgrminclude script.	15 years ago
Tom Lane	4dab3d5ae1	Change the autovacuum launcher to use WaitLatch instead of a poll loop. ... In pursuit of this (and with the expectation that WaitLatch will be needed in more places), convert the latch field that was already added to PGPROC for sync rep into a generic latch that is activated for all PGPROC-owning processes, and change many of the standard backend signal handlers to set that latch when a signal happens. This will allow WaitLatch callers to be wakened properly by these signals. In passing, fix a whole bunch of signal handlers that had been hacked to do things that might change errno, without adding the necessary save/restore logic for errno. Also make some minor fixes in unix_latch.c, and clean up bizarre and unsafe scheme for disowning the process's latch. Much of this has to be back-patched into 9.1. Peter Geoghegan, with additional work by Tom	15 years ago
Tom Lane	9f17ffd866	Measure WaitLatch's timeout parameter in milliseconds, not microseconds. ... The original definition had the problem that timeouts exceeding about 2100 seconds couldn't be specified on 32-bit machines. Milliseconds seem like sufficient resolution, and finer grain than that would be fantasy anyway on many platforms. Back-patch to 9.1 so that this aspect of the latch API won't change between 9.1 and later releases. Peter Geoghegan	15 years ago
Tom Lane	4e15a4db5e	Documentation improvement and minor code cleanups for the latch facility. ... Improve the documentation around weak-memory-ordering risks, and do a pass of general editorialization on the comments in the latch code. Make the Windows latch code more like the Unix latch code where feasible; in particular provide the same Assert checks in both implementations. Fix poorly-placed WaitLatch call in syncrep.c. This patch resolves, for the moment, concerns around weak-memory-ordering bugs in latch-related code: we have documented the restrictions and checked that existing calls meet them. In 9.2 I hope that we will install suitable memory barrier instructions in SetLatch/ResetLatch, so that their callers don't need to be quite so careful.	15 years ago
Simon Riggs	5286105800	Cascading replication feature for streaming log-based replication. ... Standby servers can now have WALSender processes, which can work with either WALReceiver or archive_commands to pass data. Fully updated docs, including new conceptual terms of sending server, upstream and downstream servers. WALSenders terminated when promote to master. Fujii Masao, review, rework and doc rewrite by Simon Riggs	15 years ago
Heikki Linnakangas	89fd72cbf2	Introduce a pipe between postmaster and each backend, which can be used to ... detect postmaster death. Postmaster keeps the write-end of the pipe open, so when it dies, children get EOF in the read-end. That can conveniently be waited for in select(), which allows eliminating some of the polling loops that check for postmaster death. This patch doesn't yet change all the loops to use the new mechanism, expect a follow-on patch to do that. This changes the interface to WaitLatch, so that it takes as argument a bitmask of events that it waits for. Possible events are latch set, timeout, postmaster death, and socket becoming readable or writeable. The pipe method behaves slightly differently from the kill() method previously used in PostmasterIsAlive() in the case that postmaster has died, but its parent has not yet read its exit code with waitpid(). The pipe returns EOF as soon as the process dies, but kill() continues to return true until waitpid() has been called (IOW while the process is a zombie). Because of that, change PostmasterIsAlive() to use the pipe too, otherwise WaitLatch() would return immediately with WL_POSTMASTER_DEATH, while PostmasterIsAlive() would claim it's still alive. That could easily lead to busy-waiting while postmaster is in zombie state. Peter Geoghegan with further changes by me, reviewed by Fujii Masao and Florian Pflug.	15 years ago
Peter Eisentraut	e2a0cb1a80	Message style and spelling improvements	15 years ago
Bruce Momjian	6560407c7d	Pgindent run before 9.1 beta2.	15 years ago
Bruce Momjian	bf50caf105	pgindent run before PG 9.1 beta 1.	15 years ago
Tom Lane	2594cf0e8c	Revise the API for GUC variable assign hooks. ... The previous functions of assign hooks are now split between check hooks and assign hooks, where the former can fail but the latter shouldn't. Aside from being conceptually clearer, this approach exposes the "canonicalized" form of the variable value to guc.c without having to do an actual assignment. And that lets us fix the problem recently noted by Bernd Helmle that the auto-tune patch for wal_buffers resulted in bogus log messages about "parameter "wal_buffers" cannot be changed without restarting the server". There may be some speed advantage too, because this design lets hook functions avoid re-parsing variable values when restoring a previous state after a rollback (they can store a pre-parsed representation of the value instead). This patch also resolves a longstanding annoyance about custom error messages from variable assign hooks: they should modify, not appear separately from, guc.c's own message about "invalid parameter value".	15 years ago
Robert Haas	240067b3b0	Merge synchronous_replication setting into synchronous_commit. ... This means one less thing to configure when setting up synchronous replication, and also avoids some ambiguity around what the behavior should be when the settings of these variables conflict. Fujii Masao, with additional hacking by me.	15 years ago
Simon Riggs	92f4786fa9	Additional test for each commit in sync rep path to plug minute ... possibility of race condition that would effect performance only. Requested by Robert Haas. Re-arrange related comments.	15 years ago
Robert Haas	727589995a	Move synchronous_standbys_defined updates from WAL writer to BG writer. ... This is advantageous because the BG writer is alive until much later in the shutdown sequence than WAL writer; we want to make sure that it's possible to shut off synchronous replication during a smart shutdown, else it might not be possible to complete the shutdown at all. Per very reasonable gripes from Fujii Masao and Simon Riggs.	15 years ago
Robert Haas	7a37900443	Make synchronous replication query cancel/die messages more consistent. ... Per a gripe from Thom Brown about my previous commit in this area, commit 9a56dc3389.	15 years ago
Robert Haas	9a56dc3389	Fix various possible problems with synchronous replication. ... 1. Don't ignore query cancel interrupts. Instead, if the user asks to cancel the query after we've already committed it, but before it's on the standby, just emit a warning and let the COMMIT finish. 2. Don't ignore die interrupts (pg_terminate_backend or fast shutdown). Instead, emit a warning message and close the connection without acknowledging the commit. Other backends will still see the effect of the commit, but there's no getting around that; it's too late to abort at this point, and ignoring die interrupts altogether doesn't seem like a good idea. 3. If synchronous_standby_names becomes empty, wake up all backends waiting for synchronous replication to complete. Without this, someone attempting to shut synchronous replication off could easily wedge the entire system instead. 4. Avoid depending on the assumption that if a walsender updates MyProc->syncRepState, we'll see the change even if we read it without holding the lock. The window for this appears to be quite narrow (and probably doesn't exist at all on machines with strong memory ordering) but protecting against it is practically free, so do that. 5. Remove useless state SYNC_REP_MUST_DISCONNECT, which isn't needed and doesn't actually do anything. There's still some further work needed here to make the behavior of fast shutdown plausible, but that looks complex, so I'm leaving it for a separate commit. Review by Fujii Masao.	15 years ago
Robert Haas	551c07d84a	Make error handling of synchronous_standby_names consistent. ... It's not a good idea to kill the postmaster just because someone muffs this, and it's not consistent with what we do for other, similar GUCs. Fujii Masao, with a bit more hacking by me	15 years ago
Robert Haas	2e019c8611	More synchronous replication typo fixes. ... Fujii Masao	15 years ago
Robert Haas	b8bb8dbf20	More synchronous replication tweaks. ... SyncRepRequested() must check not only the value of the synchronous_replication GUC but also whether max_wal_senders > 0. Otherwise, we might end up waiting for sync rep even when there's no possibility of a standby ever managing to connect. There are some existing cross-checks to prevent this, but they're not quite sufficient: the user can start the server with max_wal_senders=0, synchronous_standby_names='', and synchronous_replication=off and then subsequent make synchronous_standby_names not empty using pg_ctl reload, and then SET synchronous_standby=on, leading to an indefinite hang. Along the way, rename the global variable for the synchronous_replication GUC to match the name of the GUC itself, for clarity. Report by Fujii Masao, though I didn't use his patch.	15 years ago
Robert Haas	6436098795	Minor sync rep corrections. ... Fujii Masao, with a bit of additional wordsmithing by me.	15 years ago
Itagaki Takahiro	2d8de0a50b	Cleanup copyright years and file names in the header comments of some files.	15 years ago
Heikki Linnakangas	baabf05196	Silence compiler warning about undefined function when compiling without ... assertions.	15 years ago
Simon Riggs	966fb05b58	Add new files for syncrep missed in previous commit	15 years ago