This test measures the time needed to compress a sample file (an Ubuntu file-system image) using Zstd compression.
This application is single-threaded and was measured pinned to core 1.
Metrics (Intel) - phoronix/compress-zstdsh - pid 12103 On_CPU 0.125 On_Core 1.000 IPC 0.708 Retire 0.142 (14.2%) FrontEnd 0.028 (2.8%) Spec 0.135 (13.5%) Backend 0.695 (69.5%) Elapsed 132.63 Procs 4 Maxrss 211K Minflt 53827 Majflt 0 Inblock 0 Oublock 1596880 Msgsnd 0 Msgrcv 0 Nsignals 0 Nvcsw 3261 (48.8%) Nivcsw 3423 Utime 132.036394 Stime 0.591996 Start 528075.63 Finish 528208.26
On_Core of 100%. Otherwise an IPC of 0.71 with a high rate of backend stalls. As shown below these are most likely memory related.
Metrics (AMD) - phoronix/compress-zstdsh - pid 8564 On_CPU 0.062 On_Core 0.999 IPC 0.589 FrontCyc 0.132 (13.2%) BackCyc 0.066 (6.6%) Elapsed 165.52 Procs 4 Maxrss 211K Minflt 53830 Majflt 0 Inblock 0 Oublock 1596880 Msgsnd 0 Msgrcv 0 Nsignals 0 Nvcsw 3268 (14.6%) Nivcsw 19191 Utime 164.822151 Stime 0.539489 Start 411133.23 Finish 411298.75
IPC on AMD is slightly lower.
Process Tree - phoronix/compress-zstd
Process Tree
The process tree is simple:
12103) sh
12104) compress-zstd
12105) zstd
12106) zstd
Overall On_Core is 100%.
IPC has some noise, but otherwise is lower than average for a single-threaded application.
The largest issue are memory stalls.
on_cpu 0.124 elapsed 399.644 utime 395.101 stime 2.136 nvcsw 5834 (91.47%) nivcsw 544 (8.53%) inblock 0 onblock 4791272 retire 0.178 ms_uops 0.002 speculation 0.109 branch_misses 88.62% machine_clears 11.38% frontend 0.031 idq_uops_delivered_0 0.006 icache_stall 0.001 itlb_misses 0.000 idq_uops_delivered_1 0.010 idq_uops_delivered_2 0.017 idq_uops_delivered_3 0.029 dsb_ops 90.05% backend 0.682 resource_stalls.sb 0.003 stalls_ldm_pending 0.788 l2_refs 0.007 l2_misses 0.005 l2_miss_ratio 74.75% l3_refs 0.005 l3_misses 0.002 l3_miss_ratio 39.00%
Cache misses and memory operations are behind the memory stalls. Branch misses are a secondary issue.
Next steps: None