postgres

Commit Graph

Author	SHA1	Message	Date
Tomas Vondra	2c7ea57e56	Revert "Logical decoding of sequences" This reverts a sequence of commits, implementing features related to logical decoding and replication of sequences: - `0da92dc530` - `80901b3291` - `b779d7d8fd` - `d5ed9da41d` - `a180c2b34d` - `75b1521dae` - `2d2232933b` - `002c9dd97a` - `05843b1aa4` The implementation has issues, mostly due to combining transactional and non-transactional behavior of sequences. It's not clear how this could be fixed, but it'll require reworking significant part of the patch. Discussion: https://postgr.es/m/95345a19-d508-63d1-860a-f5c2f41e8d40@enterprisedb.com	4 years ago
Tomas Vondra	80901b3291	Add decoding of sequences to test_decoding Commit `0da92dc530` improved the logical decoding infrastructure to handle sequences, and did various changes to related parts (WAL logging etc.). But it did not include any implementation of the new callbacks added to OutputPluginCallbacks. This extends test_decoding with two callbacks to decode sequences. The decoding of sequences may be disabled using 'include-sequences', a new option of the output plugin. Author: Tomas Vondra, Cary Huang Reviewed-by: Peter Eisentraut, Hannu Krosing, Andres Freund Discussion: https://postgr.es/m/d045f3c2-6cfb-06d3-5540-e63c320df8bc@enterprisedb.com Discussion: https://postgr.es/m/1710ed7e13b.cd7177461430746.3372264562543607781@highgo.ca	4 years ago
Tom Lane	4a054069a3	Improve display of query results in isolation tests. Previously, isolationtester displayed SQL query results using some ad-hoc code that clearly hadn't had much effort expended on it. Field values longer than 14 characters weren't separated from the next field, and usually caused misalignment of the columns too. Also there was no visual separation of a query's result from subsequent isolationtester output. This made test result files confusing and hard to read. To improve matters, let's use libpq's PQprint() function. Although that's long since unused by psql, it's still plenty good enough for the purpose here. Like `741d7f104`, back-patch to all supported branches, so that this isn't a stumbling block for back-patching isolation test changes. Discussion: https://postgr.es/m/582362.1623798221@sss.pgh.pa.us	5 years ago
Thomas Munro	4c04be9b05	Introduce xid8-based functions to replace txid_XXX. The txid_XXX family of fmgr functions exposes 64 bit transaction IDs to users as int8. Now that we have an SQL type xid8 for FullTransactionId, define a new set of functions including pg_current_xact_id() and pg_current_snapshot() based on that. Keep the old functions around too, for now. It's a bit sneaky to use the same C functions for both, but since the binary representation is identical except for the signedness of the type, and since older functions are the ones using the wrong signedness, and since we'll presumably drop the older ones after a reasonable period of time, it seems reasonable to switch to FullTransactionId internally and share the code for both. Reviewed-by: Fujii Masao <masao.fujii@oss.nttdata.com> Reviewed-by: Takao Fujii <btfujiitkp@oss.nttdata.com> Reviewed-by: Yoshikazu Imai <imai.yoshikazu@fujitsu.com> Reviewed-by: Mark Dilger <mark.dilger@enterprisedb.com> Discussion: https://postgr.es/m/20190725000636.666m5mad25wfbrri%40alap3.anarazel.de	6 years ago
Andres Freund	955a684e04	Fix race condition leading to hanging logical slot creation. The snapshot assembly during the creation of logical slots relied waiting for transactions in xl_running_xacts to end, by checking for their commit/abort records. Unfortunately, despite locking, it is possible to see an xl_running_xact record listing transactions as ready, that have already WAL-logged an commit/abort record, as the locking just prevents the ProcArray to be adjusted, and the commit record has to be logged first. That lead to either delayed or hanging snapshot creation, because snapbuild.c would wait "forever" to see commit/abort records for some transactions. That hang resolved only if a xl_running_xacts record without any running transactions happened to be logged, far from certain on a busy server. It's impractical to prevent that via more heavyweight locking, the likelihood of deadlocks and significantly increased contention would be too big. Instead change the initial snapshot creation to be solely based on tracking the oldest running transaction via xl_running_xacts->oldestRunningXid - that actually ends up significantly simplifying the code. That has two disadvantages: 1) Because we cannot fully "trust" the contents of xl_running_xacts, we cannot use it to build the initial snapshot. Instead we have to wait twice for all running transactions to finish. 2) Previously a slot, unless the race occurred, could be created when the all transaction perceived as running based on commit/abort records, now we have to wait for the next xl_running_xacts record. To address that, trigger logging new xl_running_xacts record from within snapbuild.c exactly when necessary. Unfortunately snabuild.c's SnapBuild is stored on disk, one of the stupider ideas of a certain Mr Freund, so we can't change it in a minor release. As this is going to be backpatched, we have to hack around a bit to keep on-disk compatibility. A later commit will rejigger that on master. Author: Andres Freund, based on a quite different patch from Petr Jelinek Analyzed-By: Petr Jelinek Reviewed-By: Petr Jelinek Discussion: https://postgr.es/m/f37e975c-908f-858e-707f-058d3b1eb214@2ndquadrant.com Backpatch: 9.4-, where logical decoding has been introduced	9 years ago
Andres Freund	ec5896aed3	Fix several weaknesses in slot and logical replication on-disk serialization. Heikki noticed in 544E23C0.8090605@vmware.com that slot.c and snapbuild.c were missing the FIN_CRC32 call when computing/checking checksums of on disk files. That doesn't lower the the error detection capabilities of the checksum, but is inconsistent with other usages. In a followup mail Heikki also noticed that, contrary to a comment, the 'version' and 'length' struct fields of replication slot's on disk data where not covered by the checksum. That's not likely to lead to actually missed corruption as those fields are cross checked with the expected version and the actual file length. But it's wrong nonetheless. As fixing these issues makes existing on disk files unreadable, bump the expected versions of on disk files for both slots and logical decoding historic catalog snapshots. This means that loading old files will fail with ERROR: "replication slot file ... has unsupported version 1" and ERROR: "snapbuild state file ... has unsupported version 1 instead of 2" respectively. Given the low likelihood of anybody already using these new features in a production setup that seems acceptable. Fixing these issues made me notice that there's no regression test covering the loading of historic snapshot from disk - so add one. Backpatch to 9.4 where these features were introduced.	11 years ago

6 Commits (f3ed72ca0765bdd726a31b7fa20219e96baf312c)