Re: bg worker: patch 1 of 6 - permanent process
Tom Lane <tgl@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Markus Wanner <markus@bluegap.ch>
Cc: Robert Haas <robertmhaas@gmail.com>, Itagaki Takahiro <itagaki.takahiro@gmail.com>, PostgreSQL-development Hackers <pgsql-hackers@postgresql.org>
Date: 2010-08-26T19:22:22Z
Lists: pgsql-hackers
Markus Wanner <markus@bluegap.ch> writes: > On 08/26/2010 02:44 PM, Robert Haas wrote: >> On the more general topic of imessages, I had one other thought that >> might be worth considering. Instead of using shared memory, what >> about using a file that is shared between the sender and receiver? > What would that buy us? Not having to have a hard limit on the space for unconsumed messages? > The current approach uses plain spinlocks, which are more efficient. Please note the coding rule that says that the code should not execute more than a few straight-line instructions while holding a spinlock. If you're copying long messages while holding the lock, I don't think spinlocks are acceptable. regards, tom lane