From mboxrd@z Thu Jan  1 00:00:00 1970
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From: Yijing Wang <wangyijing0307 at gmail.com>
Subject: [SPDK] A question for bdev_io cache
Date: Wed, 09 Oct 2019 10:09:51 +0800
Message-ID: <56c7baa5-ee1e-2897-0be5-8890481b53cf@gmail.com>
In-Reply-To: 555b88e8-3d34-bbb1-d86c-4bcd68d195b6@gmail.com
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To: spdk@lists.01.org

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Hi James,

 =C2=A0=C2=A0=C2=A0=C2=A0 I'm a spdk developer from china, I'm sorry to dis=
turb you, =

recently I read the latest spdk bdev io code, and found that spdk =

prepopulate per-thread bdev_io cache in bdev module.

As we knew, dpdk rte_mempool_create has a parameter cache_size which =

allow users to cache some objects in local cpu,=C2=A0 my question is why yo=
u =

post the patch to create bdev io cache

in bdev own list, but not use default dpdk rte_mempool cache mechnasim=EF=
=BC=9F =

The reason is dpdk rte_mempool cache cannot prevent a bdev device in a =

thread from starvation? Since dpdk

rte_mempool cache is preserved for all users in the same cpu thread.


Thanks!

Yijing.
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