diff options
| author | Andres Freund | 2017-04-24 03:41:29 +0000 |
|---|---|---|
| committer | Andres Freund | 2017-04-27 20:13:36 +0000 |
| commit | 2bef06d51646058c6bb480fcdbffb1f0cc914fed (patch) | |
| tree | 6d344f49ba0b6e2e6568847214c85c13965bace2 /src/include | |
| parent | fa31b6f4e9696f3c9777bf4ec2faea822826ce9f (diff) | |
Preserve required !catalog tuples while computing initial decoding snapshot.
The logical decoding machinery already preserved all the required
catalog tuples, which is sufficient in the course of normal logical
decoding, but did not guarantee that non-catalog tuples were preserved
during computation of the initial snapshot when creating a slot over
the replication protocol.
This could cause a corrupted initial snapshot being exported. The
time window for issues is usually not terribly large, but on a busy
server it's perfectly possible to it hit it. Ongoing decoding is not
affected by this bug.
To avoid increased overhead for the SQL API, only retain additional
tuples when a logical slot is being created over the replication
protocol. To do so this commit changes the signature of
CreateInitDecodingContext(), but it seems unlikely that it's being
used in an extension, so that's probably ok.
In a drive-by fix, fix handling of
ReplicationSlotsComputeRequiredXmin's already_locked argument, which
should only apply to ProcArrayLock, not ReplicationSlotControlLock.
Reported-By: Erik Rijkers
Analyzed-By: Petr Jelinek
Author: Petr Jelinek, heavily editorialized by Andres Freund
Reviewed-By: Andres Freund
Discussion: https://postgr.es/m/9a897b86-46e1-9915-ee4c-da02e4ff6a95@2ndquadrant.com
Backport: 9.4, where logical decoding was introduced.
Diffstat (limited to 'src/include')
| -rw-r--r-- | src/include/replication/logical.h | 1 | ||||
| -rw-r--r-- | src/include/storage/procarray.h | 2 |
2 files changed, 2 insertions, 1 deletions
diff --git a/src/include/replication/logical.h b/src/include/replication/logical.h index f012735f14..d0b2e0bbae 100644 --- a/src/include/replication/logical.h +++ b/src/include/replication/logical.h @@ -82,6 +82,7 @@ extern void CheckLogicalDecodingRequirements(void); extern LogicalDecodingContext *CreateInitDecodingContext(char *plugin, List *output_plugin_options, + bool need_full_snapshot, XLogPageReadCB read_page, LogicalOutputPluginWriterPrepareWrite prepare_write, LogicalOutputPluginWriterWrite do_write); diff --git a/src/include/storage/procarray.h b/src/include/storage/procarray.h index 9b42e49524..805ecd25ec 100644 --- a/src/include/storage/procarray.h +++ b/src/include/storage/procarray.h @@ -88,7 +88,7 @@ extern bool TransactionIdIsInProgress(TransactionId xid); extern bool TransactionIdIsActive(TransactionId xid); extern TransactionId GetOldestXmin(Relation rel, int flags); extern TransactionId GetOldestActiveTransactionId(void); -extern TransactionId GetOldestSafeDecodingTransactionId(void); +extern TransactionId GetOldestSafeDecodingTransactionId(bool catalogOnly); extern VirtualTransactionId *GetVirtualXIDsDelayingChkpt(int *nvxids); extern bool HaveVirtualXIDsDelayingChkpt(VirtualTransactionId *vxids, int nvxids); |