Synchronized Scan
Here is the latest version of my patch that's revised according to my
discussions with Heikki and Simon:
Changes:
* uses LWLocks when accessing shared memory
* removes the "sync_seqscan_offset" feature
* uses the relfilenode as a key rather than relation OID
* fixes regression test failure
* uses a simple LRU (that stays in fixed-size shared memory) to track
the locations of other concurrent scans
For the LRU I used a doubly-linked list, which isn't strictly necessary.
However, we may decide to use a hash table for the lookup, in which case
the extra pointers will be useful.
Regards,
Jeff Davis
Attachments:
syncscan20.patchtext/x-patch; charset=UTF-8; name=syncscan20.patchDownload+404-50
Am Montag, 21. Mai 2007 00:01 schrieb Jeff Davis:
Here is the latest version of my patch that's revised according to my
discussions with Heikki and Simon:
This patch was apparently done against 8.2.4, but it doesn't apply to CVS
head.
--
Peter Eisentraut
http://developer.postgresql.org/~petere/
On Mon, 2007-05-21 at 16:03 +0200, Peter Eisentraut wrote:
Am Montag, 21. Mai 2007 00:01 schrieb Jeff Davis:
Here is the latest version of my patch that's revised according to my
discussions with Heikki and Simon:This patch was apparently done against 8.2.4, but it doesn't apply to CVS
head.
Thanks. Here's a version that applies cleanly to CVS head.
Regards,
Jeff Davis
Attachments:
syncscan20-cvshead.patchtext/x-patch; charset=utf-8; name=syncscan20-cvshead.patchDownload+404-50
Your patch has been added to the PostgreSQL unapplied patches list at:
http://momjian.postgresql.org/cgi-bin/pgpatches
It will be applied as soon as one of the PostgreSQL committers reviews
and approves it.
---------------------------------------------------------------------------
Jeff Davis wrote:
On Mon, 2007-05-21 at 16:03 +0200, Peter Eisentraut wrote:
Am Montag, 21. Mai 2007 00:01 schrieb Jeff Davis:
Here is the latest version of my patch that's revised according to my
discussions with Heikki and Simon:This patch was apparently done against 8.2.4, but it doesn't apply to CVS
head.Thanks. Here's a version that applies cleanly to CVS head.
Regards,
Jeff Davis
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--
Bruce Momjian <bruce@momjian.us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com
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