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--- dragnet:benchmarks_of_the_lotaas_pipelines [2016-08-09 15:30] – [Benchmarks for filterbank creation with psrfits2fil] Sotiris Sanidas
+++ dragnet:benchmarks_of_the_lotaas_pipelines [2017-03-08 15:27] (current) – external edit 127.0.0.1
@@ Line 72: / Line 72: @@
-psrfits2fil was executed with different numbers of parallel processes. The following plot shows the amount of time needed in order to create the fil files for various cases of parallel psrfits2fil instances
+psrfits2fil was executed with different numbers of parallel processes. The following plot shows the amount of time needed in order to create the fil files for various cases of parallel psrfits2fil instances.\\
+Using the same disk the following cases were tried: 1,3,4,5,8,12,16. Anything above 16 is just an extrapolation\\
+for 2 disks: 1,4,8,12,16,20,24,28,32
+{{dragnet:benchmarks:psrfits2fil1a.png?400}}
+Using multithreading with 2 disks, gives a smooth linear performance up to 24 cores, and then it turns slightly worse, probably due to I/O.
+Using the above results, I extrapolated the time needed with each work strategy in order to compute 32 filtebanks.\\
+{{dragnet:benchmarks:psrfits2fil1b.png?400}}
+When using the same disk, the fastest execution time is achieved having 4 psrfits2fil instances running in parallel. Above that, probably disk I/O normalises all the results and the performance decreases gradually, probably due to the increased I/O calls, since the throughput must already be saturated.\\
+Using 2 disks, the performance is significantly better, and the best results are achieved using 24 psrfits2fil instances in parallel, although the difference remains small.\\
 ==== rfifind benchmarks ====
@@ Line 91: / Line 103: @@
 {{dragnet:benchmarks:rfifind2b.png?400}}
-From the above, we can conclude that using 1 or 2 disks does not make a big difference. Also, hyperthreading works smoothly, and indeed the best strategy is to have the maximum possible number of rfifind instances running in parallel .
+From the above, we can conclude that using 1 or 2 disks does not make a big difference. Also, hyperthreading works smoothly, and indeed the best strategy is to have the maximum possible number of rfifind instances running in parallel.
+==== Cartesius Benchmarks ====
+Processing 1 full pointing on cartesius using either /dev/shm or HDDs
+{{dragnet:benchmarks:cartesius_bm1.png?400}}