Ok. There is a problem with the patches that went in between Postgres
9.4.3->9.4.4
I downgraded to Postgres 9.4.3 and everythig is normal. "Actual disk
writes" in iostat is pretty much as "Total disk writes" (between 50-100
Kbps and not in Mbps). "vmstat 1" also shows no excessive disk writes.
I am using postgres 9.4.3 on Gentoo linux along with uwsgi, python 2.7 and
nginx.
-Sushant.
On Thu, Jul 23, 2015 at 10:27 AM, <pgsql-bugs-owner@postgresql.org> wrote:
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> ---------- Forwarded message ----------
> From: sushant@indiankanoon.com
> To: pgsql-bugs@postgresql.org
> Cc:
> Date: Thu, 23 Jul 2015 04:56:17 +0000
> Subject: BUG #13515: Much higher disk writes after postgres upgrade
> 9.4.3->9.4.4
> The following bug has been logged on the website:
>
> Bug reference: 13515
> Logged by: Sushant Sinha
> Email address: sushant@indiankanoon.com
> PostgreSQL version: 9.4.4
> Operating system: Linux
> Description:
>
> After upgrade from postgres 9.4.3 to 9.4.4 I am seeing constant disk writes
> of 4-8MB/s in the background in production. I verified it using iotop and
> vmstat. iotop shows "Total Disk Write" to be minuscule (like 10-100Kbps).
> It
> is affecting runtime performance. I never noticed this issue with postgres
> 9.4.3.
>
> I increased the shared buffers from 128MB to 1GB and still didn't see any
> benefit.
>
> The website (http://indiankanoon.org) mostly uses text search with gin
> index
> and some logging of click through data. The main database is replicated
> using "streaming asynchronous replication".
>
> I am going to downgrade it to 9.4.3 to see if the upgrade was the real
> problem. But just wanted to check if anyone else noticed it.
>
>
>