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Comment by venti | Hacker News Reader

How does that compare to other cloud servers?

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

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

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).

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.

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).

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]

Didn't know about fio, thanks!

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