The vertica vioperf tool is used to determine whether the storage you are planning on using is fast enough to feed the vertica database.
The vioperf tool runs on a linux host or VM and can be pointed at any filesystem just like fio or vdbench
Simple execution of vioperf writing to the location /vertica
|
1 |
vioperf --thread-count=8 --duration=120s /vertica |
Working Set Size
Unlike traditional IO generators vioperf does not allow you to specify the workings size. The amount of data written is simply the IO rate achieved by the storage * runtime. So, fast storage with long run-times will need a lot of capacity otherwise the tool simply fills the partition and crashes!
Measurement and goodness
The primary metric is MB/s Per-Core. The idea is that you give 1 Thread per core in the system, though there is nothing stopping you from using whatever –thread-count value you like.
Although the measure is throughput, the measure (Throughput/Core) does not improve just by giving lots of concurrency. Concurrency is generated purely by the number of threads and since the measure of goodness is Throughput/Core (or per thread) it’s not possible to simply create throughput from concurrency alone.
I guess we assume that each vertica thread is synchronous. Which seems a bit odd.
Throughput compared to FIo
Compared to fio the reported throughput is lower for the same device and same degree of concurrency. Vertica continually writes, and extends the files so there is some filesystem work going on whereas fio is overwriting an existing file.
vertica iostat 64 Threads
|
1 2 3 4 5 |
Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdc 0.00 285.00 0.00 169.00 0.00 86528.00 1024.00 10.56 64.11 0.00 64.11 5.89 99.60 sde 0.00 285.00 0.00 159.00 0.00 81408.00 1024.00 21.55 127.55 0.00 127.55 6.29 100.00 md1 0.00 0.00 0.00 605.00 0.00 163840.00 541.62 0.00 0.00 0.00 0.00 0.00 0.00 |
fio iostat iodepth=64
|
1 2 3 4 5 |
Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sdc 0.00 0.00 0.00 219.00 0.00 112128.00 1024.00 63.50 285.05 0.00 285.05 4.57 100.00 sde 0.00 0.00 0.00 219.00 0.00 112128.00 1024.00 0.45 2.04 0.00 2.04 2.04 44.60 md1 0.00 0.00 0.00 438.00 0.00 224256.00 1024.00 0.00 0.00 0.00 0.00 0.00 0.00 |
fio 1 thread 1M sequential write
|
1 2 3 4 5 6 7 8 |
avg-cpu: %user %nice %system %iowait %steal %idle 3.30 0.03 4.16 9.53 0.00 82.98 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sda 0.00 0.40 0.00 4.00 0.00 23.50 11.75 0.01 1.70 0.00 1.70 0.20 0.08 dm-1 0.00 0.00 0.00 2.00 0.00 9.50 9.50 0.00 2.00 0.00 2.00 0.20 0.04 nvme0n1 0.00 0.20 0.00 4695.40 0.00 2403432.80 1023.74 1.28 0.27 0.00 0.27 0.18 86.20 |
Vertica IOstat 1 thread
|
1 2 3 4 5 6 7 |
avg-cpu: %user %nice %system %iowait %steal %idle 11.97 0.03 3.71 1.20 0.00 83.09 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sda 0.00 0.00 0.00 2.20 0.00 16.80 15.27 0.00 0.64 0.00 0.64 0.64 0.14 nvme0n1 0.00 79.60 2.60 875.20 10.40 308546.40 703.02 0.28 0.32 0.15 0.32 0.19 16.24 |
vioperf with –disable-crc
|
1 2 3 4 5 6 7 8 |
avg-cpu: %user %nice %system %iowait %steal %idle 2.46 0.05 6.55 8.09 0.00 82.85 Device: rrqm/s wrqm/s r/s w/s rkB/s wkB/s avgrq-sz avgqu-sz await r_await w_await svctm %util sda 0.00 0.00 0.00 0.60 0.00 2.40 8.00 0.00 1.67 0.00 1.67 1.00 0.06 dm-1 0.00 0.00 0.00 0.40 0.00 1.60 8.00 0.00 2.00 0.00 2.00 1.00 0.04 nvme0n1 0.00 158.40 5.20 1786.60 20.80 630392.80 703.67 1.46 0.81 2.85 0.81 0.46 82.44 |
