From: Michal Hocko <mhocko@kernel.org>
To: Pankaj Suryawanshi <pankaj.suryawanshi@einfochips.com>
Cc: "linux-mm@kvack.org" <linux-mm@kvack.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"minchan@kernel.org" <minchan@kernel.org>,
Kirill Tkhai <ktkhai@virtuozzo.com>
Subject: Re: mm/cma.c: High latency for cma allocation
Date: Mon, 18 Mar 2019 14:07:57 +0100 [thread overview]
Message-ID: <20190318130757.GG8924@dhcp22.suse.cz> (raw)
In-Reply-To: <SG2PR02MB3098E44824F5AA69BC04F935E8470@SG2PR02MB3098.apcprd02.prod.outlook.com>
On Mon 18-03-19 12:58:28, Pankaj Suryawanshi wrote:
> Hello,
>
> I am facing issue of high latency in CMA allocation of large size buffer.
>
> I am frequently allocating/deallocation CMA memory, latency of allocation is very high.
>
> Below are the stat for allocation/deallocation latency issue.
>
> (390100 kB), latency 29997 us
> (390100 kB), latency 22957 us
> (390100 kB), latency 25735 us
> (390100 kB), latency 12736 us
> (390100 kB), latency 26009 us
> (390100 kB), latency 18058 us
> (390100 kB), latency 27997 us
> (16 kB), latency 560 us
> (256 kB), latency 280 us
> (4 kB), latency 311 us
>
> I am using kernel 4.14.65 with android pie(9.0).
>
> Is there any workaround or solution for this(cma_alloc latency) issue ?
Do you have any more detailed information on where the time is spent?
E.g. migration tracepoints?
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2019-03-18 13:08 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-03-18 12:58 Pankaj Suryawanshi
2019-03-18 13:07 ` Michal Hocko [this message]
2019-03-18 13:28 ` [External] " Pankaj Suryawanshi
2019-03-18 13:42 ` Michal Hocko
2019-03-18 14:02 ` Pankaj Suryawanshi
2019-03-18 14:29 ` Michal Hocko
2019-03-19 10:29 ` Pankaj Suryawanshi
2019-03-19 11:45 ` Pankaj Suryawanshi
2019-03-21 9:53 ` Michal Hocko
2019-03-18 13:30 ` Pankaj Suryawanshi
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