tuocmd
54 Posts
Quote from tuocmd on July 29, 2021, 1:25 pm
i build petasan for vmware virtualization system
Requires read/write speed of about 500MB/s
with 3 nodes using hdd, do you have any recommendations?
i build petasan for vmware virtualization system
Requires read/write speed of about 500MB/s
with 3 nodes using hdd, do you have any recommendations?
admin
2,930 Posts
Quote from admin on July 29, 2021, 2:27 pm
Typically we recommend SSD for virtualization.
To achieve 500 MB/s with HDD, there are many factors : what is the average block size for your workloads ? You can measure this from the throughput and iops charts on the dashboard (divide first by second), many virtualisation loads have small block size. Assume 16KB block size: you need 30K iops to reach 500 MB/s, for writes with replication x3 you need 90K iops, that is assuming you use external SSD journal for metadata else you will further double the required iops, such iops are not possible from HDDs on 3 nodes such as 60-70 devices, each HDD can give from 80-150 iops.
Typically we recommend SSD for virtualization.
To achieve 500 MB/s with HDD, there are many factors : what is the average block size for your workloads ? You can measure this from the throughput and iops charts on the dashboard (divide first by second), many virtualisation loads have small block size. Assume 16KB block size: you need 30K iops to reach 500 MB/s, for writes with replication x3 you need 90K iops, that is assuming you use external SSD journal for metadata else you will further double the required iops, such iops are not possible from HDDs on 3 nodes such as 60-70 devices, each HDD can give from 80-150 iops.
tuocmd
54 Posts
Quote from tuocmd on July 29, 2021, 2:56 pm
I use 3 nodes, each node1 2TB SSD and 4 HDD 2TB, in a ratio of 4:1
Do you have any other ideas?
I use 3 nodes, each node1 2TB SSD and 4 HDD 2TB, in a ratio of 4:1
Do you have any other ideas?
