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From: Cheng Kevin <k5896246@gmail.com>
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Subject: [dpdk-dev] DPDK testpmd, Virtual Disk IO limitation
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Hi all,

   I am a beginner of DPDK. Recently, i am interest in DPDK vHost app -
testpmd.

   And i have been tracing on testpmd.c and iofwd.c for a while.

   Also add some code inside iofwd.c for storing the payload of packets.

   Everything goes fine, and the performance is great as expected.

   But when i use fwrite to store the payload into a file,

   the performance decrease from 800mbps to 3mbps (input stream is 1 Gbps).

   Is is caused by the limitation of Virtual Disk IO? How can i solve it?

   I have tried to search the answer, some people say "pthread" might solve
the problem.

   Can someone give me some hint, i really appreciate for your help.


Best Regard,

Kevin Cheng