On 9/18/15 5:05 AM, Shulgin, Oleksandr wrote:
It should not be true - the data sender create DSM and fills it.
Then set caller slot and send signal to caller. Caller can free DSM
any time, because data sender send newer touch it.
But the requester can timeout on waiting for reply and exit before it
sees the reply DSM. Actually, I now don't even think a backend can free
the DSM it has not created. First it will need to attach it,
effectively increasing the refcount, and upon detach it will only
decrease the refcount, but not actually release the segment...
So this has to be the responsibility of the reply sending backend in the
end: to create and release the DSM *at some point*.
What's wrong with just releasing it at the end of the statement? When
the statement is done there's no point to reading it asynchronously anymore.
--
Jim Nasby, Data Architect, Blue Treble Consulting, Austin TX
Experts in Analytics, Data Architecture and PostgreSQL
Data in Trouble? Get it in Treble! http://BlueTreble.com
--
Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-hackers
