On Sat, 15 Jan 2022 at 22:41, Gibson, Thomas <thomas.gibson@xxxxxxx> wrote:
>
> I wasn't sure if I should reply to you directly or not. So I did for now.
> But I cc'c the fio mailing list as well.
>
> I've attached a test data tarfile on the fio test runs for each fio test.
> tom...
>From SSSTC_CVB-8D120_FW_CZJG801_2ndrun_r640-randrd_seqwr.txt:
[...]
SSSTC_CVB-8D120_FW_CZJG801_2ndrun_r640-RandRd: (groupid=0, jobs=1):
err= 0: pid=42215: Mon Dec 20 16:53:45 2021
read: IOPS=597, BW=146MiB/s (153MB/s)(1026GiB/7200022msec)
slat (nsec): min=5512, max=99489, avg=8598.67, stdev=981.29
clat (usec): min=1156, max=329247, avg=26747.47, stdev=8216.72
lat (usec): min=1223, max=329255, avg=26756.16, stdev=8216.72
[...]
cpu : usr=0.15%, sys=0.64%, ctx=4305429, majf=0, minf=1267
SSSTC_CVB-8D120_FW_CZJG801_2ndrun_r640-SeqWr: (groupid=0, jobs=1):
err= 0: pid=42216: Mon Dec 20 16:53:45 2021
write: IOPS=597, BW=146MiB/s (153MB/s)(1026GiB/7200021msec)
slat (usec): min=7, max=143, avg=14.13, stdev= 2.23
clat (msec): min=9, max=329, avg=26.74, stdev= 8.21
lat (msec): min=9, max=329, avg=26.76, stdev= 8.21
[...]
cpu : usr=0.51%, sys=0.59%, ctx=4137284, majf=0, minf=270
[...]
Disk stats (read/write):
sde: ios=4305116/4304491, merge=0/0, ticks=115166190/115134060,
in_queue=18446744069644883850, util=100.00%
You have plenty of CPU left but your disk utilisation is 100% so for
whatever reason the disk can't accept more I/O. Your problem is that
for whatever reason something below the kernel is bottlenecking...
My only thought is maybe your mixed workloads are better at exhausting
the disk's cache than a solo workload does?
--
Sitsofe
