Станислав
Недавно вопросом задавался, хотел узнать сколько из арк может выдать Epyc 7F52 в 8-канальном режиме. Если не использовать сжатие, то результат был следующим и всё упиралось в производительность ЦП:
root@pc:~# fio fio.ini
write: (g=0): rw=read, bs=(R) 1024KiB-1024KiB, (W) 1024KiB-1024KiB, (T) 1024KiB-1024KiB, ioengine=libaio, iodepth=1
...
fio-3.25
Starting 47 processes
Jobs: 47 (f=47): [R(47)][100.0%][r=82.6GiB/s][r=84.6k IOPS][eta 00m:00s]
write: (groupid=0, jobs=47): err= 0: pid=2380076: Mon Dec 11 00:01:52 2023
  read: IOPS=87.3k, BW=85.3GiB/s (91.6GB/s)(853GiB/10003msec)
    slat (usec): min=73, max=48881, avg=534.59, stdev=953.43
    clat (nsec): min=641, max=16384k, avg=1594.93, stdev=36037.08
     lat (usec): min=74, max=48887, avg=536.56, stdev=954.81
    clat percentiles (nsec):
     |  1.00th=[   764],  5.00th=[   844], 10.00th=[   884], 20.00th=[   932],
     | 30.00th=[   980], 40.00th=[  1048], 50.00th=[  1128], 60.00th=[  1240],
     | 70.00th=[  1400], 80.00th=[  1656], 90.00th=[  2192], 95.00th=[  2960],
     | 99.00th=[  5344], 99.50th=[  6688], 99.90th=[ 11712], 99.95th=[ 15040],
     | 99.99th=[136192]
   bw (  MiB/s): min=76800, max=95299, per=4.31%, avg=87646.99, stdev=91.81, samples=893
   iops        : min=76790, max=95287, avg=87642.89, stdev=91.84, samples=893
  lat (nsec)   : 750=0.62%, 1000=31.41%
  lat (usec)   : 2=55.57%, 4=10.09%, 10=2.17%, 20=0.13%, 50=0.01%
  lat (usec)   : 100=0.01%, 250=0.01%, 500=0.01%, 750=0.01%, 1000=0.01%
  lat (msec)   : 2=0.01%, 4=0.01%, 10=0.01%, 20=0.01%
  cpu          : usr=0.52%, sys=59.95%, ctx=257025, majf=0, minf=39045
  IO depths    : 1=100.0%, 2=0.0%, 4=0.0%, 8=0.0%, 16=0.0%, 32=0.0%, >=64=0.0%
     submit    : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     complete  : 0=0.0%, 4=100.0%, 8=0.0%, 16=0.0%, 32=0.0%, 64=0.0%, >=64=0.0%
     issued rwts: total=873364,0,0,0 short=0,0,0,0 dropped=0,0,0,0
     latency   : target=0, window=0, percentile=100.00%, depth=1
Run status group 0 (all jobs):
   READ: bw=85.3GiB/s (91.6GB/s), 85.3GiB/s-85.3GiB/s (91.6GB/s-91.6GB/s), io=853GiB (916GB), run=10003-10003msec