Den tors 3 mars 2022 kl 14:02 skrev Mihai Popescu <mih...@gmail.com>: > I am trying to test some disk i/o speeds and I am stumbled on two questions: > 1. Does it matter if I set in BIOS Legacy or AHCI for the drive, > regarding the read/write performance?
Probably yes. AHCI will be better if it works. > 2. Can you suggest a sane disk I/O benchmark, writing from RAM to disk > (i.e. cp /dev/null ....)? > https://openports.pl/path/benchmarks/fio To test perf on many small IO (measuring iops basically) run: fio --name=random-write --rw=write --bs=4k --numjobs=2 --size=1g --iodepth=16 --runtime=60 --time_based --end_fsync=1 To test large-IO perf: fio --name=random-write --rw=write --bs=1M --numjobs=1 --size=1g --iodepth=1 --runtime=60 --time_based --end_fsync=1 Look for the result in the post-run report, for small IO it can be write: IOPS=37.8k, BW=148MiB/s (155MB/s) and for larger writes write: IOPS=253, BW=253MiB/s (266MB/s) > I am on snapshots for amd64 and I think i have a really slow writing > to disk on OpenBSD only. Might be worth testing mount flags like softdep or (shudder) async if the data is backed up and not very important. -- May the most significant bit of your life be positive.
