From: Justin Pryzby <pryzby@telsasoft.com>
To: Don Seiler <don@seiler.us>
Cc: pgsql-performance@lists.postgresql.org
Subject: Re: High kswapd
Date: Mon, 13 Apr 2020 09:42:54 -0500
Message-ID: <20200413144254.GS2228@telsasoft.com> (raw)
In-Reply-To: <CAHJZqBCWEk6-0NG9bQ8XWRaRz97ppPh=ZZZ89Ykvkn+EUHSNcg@mail.gmail.com>
References: <CAHJZqBCWEk6-0NG9bQ8XWRaRz97ppPh=ZZZ89Ykvkn+EUHSNcg@mail.gmail.com>
On Mon, Apr 13, 2020 at 09:34:23AM -0500, Don Seiler wrote:
> Good morning,
>
> Ubuntu 16.04.6 LTS
> PostgreSQL 9.6.5
>
> On one of our database servers, we're regularly seeing kswapd at the top of
> "top" output, regularly using over 50 %CPU. We should have well over 80GB
> of available memory according to "free -m".
Do you have THP enabled? Or KSM ?
tail /sys/kernel/mm/ksm/run /sys/kernel/mm/transparent_hugepage/khugepaged/defrag /sys/kernel/mm/transparent_hugepage/enabled /sys/kernel/mm/transparent_hugepage/defrag
https://www.postgresql.org/message-id/20170718180152.GE17566%40telsasoft.com
--
Justin
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To: pgsql-performance@postgresql.org
Cc: pryzby@telsasoft.com, don@seiler.us, pgsql-performance@lists.postgresql.org
Subject: Re: High kswapd
In-Reply-To: <20200413144254.GS2228@telsasoft.com>
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