3 ms·
I got the same runaround with their VPS service. I started seeing really high disk latency - on the order of tens of seconds to create a file. I emailed them,
by swalberg 16y ago
I got the same runaround with their VPS service. I started seeing really high disk latency - on the order of tens of seconds to create a file. I emailed them, along with the results of a script that measured how long it took to create a new file over time.
First they told me that they checked and everything was OK, maybe I should contact someone who knows about systems administration. Then they said the performance I was seeing was within their acceptable standards.
I asked them for their standards, they said they didn't have any published standards.
Thank goodness I found Linode.
- cperciva 16y agoI started seeing really high disk latency - on the order of tens of seconds to create a file. That's not disk latency. That's filesystem latency. It's entirely possible that the disk latency was high, but you really should have measured it directly to rule out filesystem problems.
- swalberg 16y agoI would have loved to do more in depth measurement, but I couldn't get to any disk stats under /proc. Even iostat was crippled. I'm also not sure the distinction was that important in that case. With their VPS implementation there were no knobs I could turn. The root cause of the problem had to be on their side of the fence. "Measure with a micrometer. Mark with chalk. Cut with axe"
- cperciva 16y agoWell, one common issue is filesystems slowing down if data structures (e.g. directories) get big. Creating a single file doesn't take a constant number of disk operations.