From: | "Daniel Verite" <daniel(at)manitou-mail(dot)org> |
---|---|
To: | "Magnus Hagander" <magnus(at)hagander(dot)net> |
Cc: | "Peter Eisentraut" <peter(dot)eisentraut(at)2ndquadrant(dot)com>,"Christoph Berg" <myon(at)debian(dot)org>,"Andrew Dunstan" <andrew(at)dunslane(dot)net>,"Tom Lane" <tgl(at)sss(dot)pgh(dot)pa(dot)us>,"Robert Haas" <robertmhaas(at)gmail(dot)com>,"Jakob Egger" <jakob(at)eggerapps(dot)at>,"PostgreSQL Hackers" <pgsql-hackers(at)postgresql(dot)org> |
Subject: | Re: sslmode=require fallback |
Date: | 2016-07-20 12:55:48 |
Message-ID: | 5f717e36-1c80-4fd5-b9ff-17d76469d5c6@mm |
Views: | Raw Message | Whole Thread | Download mbox | Resend email |
Thread: | |
Lists: | pgsql-hackers |
Magnus Hagander wrote:
> > I don't understand why you want to change the default. Is it for
> > performance? Has it been measured?
> >
> >
> Yes. I've run into it multiple times, but I haven't specifically measured
> it. But I've had more than one situation where turning it off has
> completely removed a performance problem.
Here's a test case retrieving 133000 rows representing
100Mbytes of text, that shows a 4x slowdown with ssl.
ssl_renegotiation_limit is set to 0 and the cache is warmed up
by repeated executions.
Without SSL:
$ time psql -At "postgresql://localhost/mlists?sslmode=disable"\
-c "select subject from mail" -o /dev/null
real 0m1.359s
user 0m0.544s
sys 0m0.084s
With SSL:
$ time psql -At "postgresql://localhost/mlists?sslmode=require"\
-c "select subject from mail" -o /dev/null
real 0m5.395s
user 0m1.080s
sys 0m0.116s
The CPU is Intel(R) Xeon(R) CPU E31230 @ 3.20GHz, OS is Debian7
with kernel 3.2.0-4.
Personally I think that TLS for local networking is wrong as a default, and
it's unfortunate that distros like Debian/Ubuntu end up using that.
Best regards,
--
Daniel Vérité
PostgreSQL-powered mailer: http://www.manitou-mail.org
Twitter: @DanielVerite
From | Date | Subject | |
---|---|---|---|
Next Message | Kevin Grittner | 2016-07-20 13:37:59 | Re: Re: [COMMITTERS] pgsql: Avoid extra locks in GetSnapshotData if old_snapshot_threshold < |
Previous Message | Masahiko Sawada | 2016-07-20 12:19:47 | Re: Adjust recovery test file name |