diff options
| author | Robert Haas | 2017-03-23 18:08:23 +0000 |
|---|---|---|
| committer | Robert Haas | 2017-03-23 18:26:31 +0000 |
| commit | ea42cc18c35381f639d45628d792e790ff39e271 (patch) | |
| tree | 223916f28189cb8fb5b40793ff563928795f62ca /src/backend/access/transam/transam.c | |
| parent | 50c956add83963d7bbb367dd0b879fccddebd623 (diff) | |
Track the oldest XID that can be safely looked up in CLOG.
This provides infrastructure for looking up arbitrary, user-supplied
XIDs without a risk of scary-looking failures from within the clog
module. Normally, the oldest XID that can be safely looked up in CLOG
is the same as the oldest XID that can reused without causing
wraparound, and the latter is already tracked. However, while
truncation is in progress, the values are different, so we must
keep track of them separately.
Craig Ringer, reviewed by Simon Riggs and by me.
Discussion: http://postgr.es/m/CAMsr+YHQiWNEi0daCTboS40T+V5s_+dst3PYv_8v2wNVH+Xx4g@mail.gmail.com
Diffstat (limited to 'src/backend/access/transam/transam.c')
| -rw-r--r-- | src/backend/access/transam/transam.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/src/backend/access/transam/transam.c b/src/backend/access/transam/transam.c index b91a259e80..562b53be9a 100644 --- a/src/backend/access/transam/transam.c +++ b/src/backend/access/transam/transam.c @@ -119,7 +119,7 @@ TransactionLogFetch(TransactionId transactionId) * True iff transaction associated with the identifier did commit. * * Note: - * Assumes transaction identifier is valid. + * Assumes transaction identifier is valid and exists in clog. */ bool /* true if given transaction committed */ TransactionIdDidCommit(TransactionId transactionId) @@ -175,7 +175,7 @@ TransactionIdDidCommit(TransactionId transactionId) * True iff transaction associated with the identifier did abort. * * Note: - * Assumes transaction identifier is valid. + * Assumes transaction identifier is valid and exists in clog. */ bool /* true if given transaction aborted */ TransactionIdDidAbort(TransactionId transactionId) |