4 ms·

I made a habit out of measuring the disk performance of cloud servers, so here it is: ubuntu@instantcloud:~$ dd bs=1M count=1024 if=/dev/zero of=test conv=fd

• venti 12y ago
  How does that compare to other cloud servers?
  • growt 12y ago
    You can read my comment history for exact numbers. But for SSD storage it's not very good. Better than amazon EC2 though (t2 instance).
    • edouardb 12y ago
      You should have a look to the IOPS instead bandwidth root@instantcloud:~# fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test --filename=test --bs=4k --iodepth=16 --size=4G --readwrite=randwrite test: (g=0): rw=randwrite, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=16 fio-2.1.11 Starting 1 process Jobs: 1 (f=1): [w(1)] [100.0% done] [0KB/18714KB/0KB /s] [0/4678/0 iops] [eta 00m:00s] root@instantcloud:~# fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test --filename=test --bs=4k --iodepth=16 --size=4G --readwrite=randread test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=16 fio-2.1.11 Starting 1 process Jobs: 1 (f=1): [r(1)] [100.0% done] [22307KB/0KB/0KB /s] [5576/0/0 iops] [eta 00m:00s]
      • buster 12y ago
        Didn't know about fio, thanks!
    • deleted 12y ago
      [deleted]
  • rshm 12y ago
    Tested on random instance, without any io intensive application running VULTR 2 GB INSTANCE dd bs=1M count=1024 if=/dev/zero of=test conv=fdatasync 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB) copied, 8.11451 s, 132 MB/s hdparm -tT /dev/vda /dev/vda: Timing cached reads: 25106 MB in 2.00 seconds = 12568.51 MB/sec Timing buffered disk reads: 496 MB in 3.02 seconds = 164.16 MB/sec DIGITALOCEAN 2GB INSTANCE hdparm -tT /dev/vda Timing cached reads: 8926 MB in 2.00 seconds = 4468.52 MB/sec Timing buffered disk reads: 542 MB in 3.00 seconds = 180.43 MB/sec dd bs=1M count=1024 if=/dev/zero of=test conv=fdatasync 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB) copied, 32.0005 s, 33.6 MB/s
    • antouank 12y ago
      Did the same test on a VM I have in DigitalOcean... ( Ubuntu, 512 MB droplet ) ~# dd bs=1M count=1024 if=/dev/zero of=test conv=fdatasync 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB) copied, 2.35872 s, 455 MB/s
      • hobarrera 12y ago
        Add four spaces at the start of a line to mark it as code (both to avoid lines being merged and fixed-width font). (yes: it's just markdown here).
    • reidrac 12y ago
      I'm not sure how good is the test as it depends on the IO levels of the host where the VM instance is running. This is a 1GB Debian Wheezy instance with regular HDD in Memset [1]: dd bs=1M count=1024 if=/dev/zero of=test conv=fdatasync 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB) copied, 17.7142 s, 60.6 MB/s I checked the host and its load is average. DO's 33.6 MB/s sounds poor. [1] disclaimer: Memset hosting is my employer, I built some of this; but this is an honest test (personal VM running several services). EDIT: formatting EDIT 2: same test on a VM with SSD disk: dd bs=1M count=1024 if=/dev/zero of=test conv=fdatasync 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB) copied, 3.48953 s, 308 MB/s Again, the host has average load.
• mrmondo 12y ago
  FYI - dd is not an effective way of measuring disk performance. I'd recommend using fio to do this using libaio and direct disk reads/writes, and IOPing for basic latency tests: * Random 4k read test for flash storage: fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test \ --filename=test --bs=4k --iodepth=128 --size=5G --numjobs=12 --norandommap \ --readwrite=randread * And writes: fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test \ --filename=test --bs=4k --iodepth=128 --size=5G --numjobs=12 --norandommap \ --readwrite=randwrite --- Here's an example here is a test storage unit I'm logged into at work right now (NOTE: THIS IS NOT ON INSTANTCLOUD!): root@s1-san5:~ # fio --randrepeat=1 --ioengine=libaio --direct=1 --gtod_reduce=1 --name=test \ --filename=/dev/md200 --bs=4k --iodepth=128 --size=5G --numjobs=12 --norandommap \ --readwrite=randread test: (g=0): rw=randread, bs=4K-4K/4K-4K/4K-4K, ioengine=libaio, iodepth=128 ... Run status group 0 (all jobs): READ: io=61440MB, aggrb=2339.7MB/s, minb=199652KB/s, maxb=200362KB/s, mint=26167msec, maxt=26260msec Disk stats (read/write): md100: ios=15636294/0, merge=0/0, ticks=0/0, in_queue=1581403800, util=100.00%, aggrios=7864320/0, aggrmerge=0/0, aggrticks=128880/0, aggrin_queue=131372, aggrutil=100.00% nvme0n1: ios=7576253/0, merge=0/0, ticks=123812/0, in_queue=125748, util=100.00% nvme1n1: ios=8152387/0, merge=0/0, ticks=133948/0, in_queue=136996, util=100. While the test is running is you'll see the storage performance (Note the MB/s in the third [] and iops in the fourth []): Jobs: 12 (f=12): [r(12)] [12.3% done] [2537MB/0KB/0KB /s] [650K/0/0 iops] [eta 00m:50s] And when it's completed: * Throughput: aggrb=2339.7MB/s * IOs (Read in this case): ios=15636294/0 And then with IOPing to test latency: * Here's an example of really bad storage latency on my crappy old rotational RAID array at home: root@nas:/mnt/raid# ioping /dev/md0 4 KiB from /dev/md0 (block device 7.28 TiB): request=1 time=27.2 ms 4 KiB from /dev/md0 (block device 7.28 TiB): request=2 time=15.7 ms * Here's an example of pretty good storage latency on my new storage at work: root@s1-san5:~ # ioping /dev/md200 4 KiB from /dev/md200 (block device 1.09 TiB): request=1 time=136 us 4 KiB from /dev/md200 (block device 1.09 TiB): request=2 time=124 us 4 KiB from /dev/md200 (block device 1.09 TiB): request=3 time=112 us * And one more on a VM with storage provisioned over iSCSI to a very slow rotational storage array that's quite busy: root@nagios:~ # ioping /dev/xvda 4096 bytes from /dev/xvda (device 15.0 Gb): request=1 time=11.6 ms 4096 bytes from /dev/xvda (device 15.0 Gb): request=2 time=0.2 ms 4096 bytes from /dev/xvda (device 15.0 Gb): request=3 time=7.1 ms 4096 bytes from /dev/xvda (device 15.0 Gb): request=4 time=1.2 ms --- OK So let's try this on instantcloud.io / scaleway: * IOP/s - Random 4k reads: bs: 12 (f=12): [r(12)] [0.5% done] [31050KB/0KB/0KB /s] [7762/0/0 iops] [eta 37m:32s] * IOP/s - Random 4k writes: Jobs: 12 (f=12): [w(12)] [0.2% done] [0KB/7848KB/0KB /s] [0/1962/0 iops] [eta 02h:29m:10s] * Latency: root@instantcloud:~# ioping /dev/nbd0 4.0 KiB from /dev/nbd0 (device 46.6 GiB): request=1 time=1.4 ms 4.0 KiB from /dev/nbd0 (device 46.6 GiB): request=2 time=1.4 ms 4.0 KiB from /dev/nbd0 (device 46.6 GiB): request=3 time=1.4 ms 4.0 KiB from /dev/nbd0 (device 46.6 GiB): request=4 time=2.8 ms Conclusion: Good performance for small arm devices but not even close to even a single entry-level consumer grade SATA SSD.
• hobarrera 12y ago
  That's rather poor, considering my laptop with FDE does about 50% faster: ▶ dd bs=1M count=1024 if=/dev/zero of=test conv=fdatasync 1024+0 records in 1024+0 records out 1073741824 bytes (1.1 GB) copied, 7.32253 s, 147 MB/s