[HDFS-6080] Improve NFS gateway performance by making rtmax and wtmax configurable

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 2.4.0
• Component/s: nfs, performance
• Hadoop Flags: Reviewed
• Assignee: Abin Shahab
• Reporter: Abin Shahab
• Created: 09/Mar/14 02:53
• Updated: 10/Apr/14 13:11
• Resolved: 13/Mar/14 21:12

Description

Right now rtmax and wtmax are hardcoded in RpcProgramNFS3. These dictate the maximum read and write capacity of the server. Therefore, these affect the read and write performance.

We ran performance tests with 1mb, 100mb, and 1GB files. We noticed significant performance decline with the size increase when compared to fuse. We realized that the issue was with the hardcoded rtmax size(64k).
When we increased the rtmax to 1MB, we got a 10x improvement in performance.

NFS reads:
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File	Size	Run 1	Run 2	Run 3	Average	Std. Dev.
testFile100Mb	104857600	23.131158137	19.24552955	19.793332866	20.723340184333335	1.7172094782219731
testFile1Gb	1073741824	219.108776636	201.064032255	217.433909843	212.53557291133333	8.14037175506561
testFile1Mb	1048576	0.330546906	0.256391808	0.28730168	0.2914134646666667	0.030412987573361663

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Fuse reads:
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File	Size	Run 1	Run 2	Run 3	Average	Std. Dev.
testFile100Mb	104857600	2.394459443	2.695265191	2.50046517	2.5300632679999997	0.12457410127142007
testFile1Gb	1073741824	25.03324924	24.155102554	24.901525525	24.696625772999997	0.386672412437576
testFile1Mb	1048576	0.271615094	0.270835986	0.271796438	0.2714158393333333	0.0004166483951065848

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(NFS read after rtmax = 1MB)
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File	Size	Run 1	Run 2	Run 3	Average	Std. Dev.
testFile100Mb	104857600	3.655261869	3.438676067	3.557464787	3.5504675743333336	0.0885591069882058
testFile1Gb	1073741824	34.663612417	37.32089122	37.997718857	36.660740831333335	1.4389615098060426
testFile1Mb	1048576	0.115602858	0.106826253	0.125229976	0.11588636233333334	0.007515962395481867

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