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NFSv4 performance

Updated on Mon, 2025-02-03 13:59. Originally created by jeromel on 2025-02-03 12:08.

Single node performance
 
I used iozone for performance testing purposes but used a single node so far. Tests were simple, do 1, 2, 4, 8, 16 processes and measure average + graph. 

Since we have a limited number of interactive nodes, this test tells how much things could slow down with concurrency on a single node. 
To be sure the performance is indeed close to 600 MB/sec single thread, I did a dd test and it found 436 MB/s (I can believe in the 592 then).

Processes Readers Reader / thread (MB/sec) Initial writers Initial writers / thread (MB/sec)
1 188994.22 185 606677.81 592
2 507448.75 248 1827691.56 892
4 299481.93 73 2488218.81 607
8 357638.75 44 1407643.56 172
16 661923.67 40 1004270.04 61




Performance per thread drops rapidly with the number of threads. This means that users will feel a significant slow down as the number of users and operations will increase.

 

DD test from a few nodes

To make the result more accurate, 10 loops were made (11 GB file) and the tests were made from respectively 1, 2 and 4 distinct nodes. This shows a different picture. Performance seems fine a-priori and scales as a function of node (with error bars not presented in this cheap spreadsheet but the standard deviation is ~ 80 for each value).



 
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