Re: profiling connection overhead

From: "Kevin Grittner" <Kevin(dot)Grittner(at)wicourts(dot)gov>
To: "Jeff Janes" <jeff(dot)janes(at)gmail(dot)com>, "Robert Haas" <robertmhaas(at)gmail(dot)com>
Cc: "Andres Freund" <andres(at)anarazel(dot)de>, "Heikki Linnakangas" <heikki(dot)linnakangas(at)enterprisedb(dot)com>, "Bruce Momjian" <bruce(at)momjian(dot)us>, <pgsql-hackers(at)postgresql(dot)org>,"Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Subject: Re: profiling connection overhead
Date: 2010-12-01 15:26:24
Message-ID: 4CF614C00200002500038000@gw.wicourts.gov
Views: Raw Message | Whole Thread | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Robert Haas <robertmhaas(at)gmail(dot)com> wrote:
> Jeff Janes <jeff(dot)janes(at)gmail(dot)com> wrote:

>> Oracle's backend start up time seems to be way higher than PG's.

> Interesting. How about MySQL and SQL Server?

My recollection of Sybase ASE is that establishing a connection
doesn't start a backend or even a thread. It establishes a network
connection and associates network queues and a connection context
structure with it. "Engine" threads with CPU affinity (and a few
miscellaneous "worker" threads, too, if I remember right) do all the
work in a queue-based fashion.

Last I worked with MS SQL Server it was based on the Sybase code and
therefore worked the same way. I know they've made a lot of changes
in the last five years (including switching to MVCC and adding
snapshot isolation in addition to the already-existing serializable
isolation), so I don't know whether connection startup cost has
changed along the way.

-Kevin

In response to

Browse pgsql-hackers by date

  From Date Subject
Next Message Tom Lane 2010-12-01 15:36:50 Re: KNNGIST next step: adjusting indexAM API
Previous Message Dimitri Fontaine 2010-12-01 15:24:17 Re: KNNGIST next step: adjusting indexAM API