[HN Gopher] What does I/O bound mean? ___________________________________________________________________ What does I/O bound mean? Author : higerordermap Score : 10 points Date : 2020-10-01 08:05 UTC (14 hours ago) (HTM) web link (erikengbrecht.blogspot.com) (TXT) w3m dump (erikengbrecht.blogspot.com) | btrask wrote: | Here is a recent HN discussion on this topic: | https://news.ycombinator.com/item?id=24519786 | | My current answer is... it's complicated. | staticassertion wrote: | I was only commenting on this on HN just the other day. When most | people say IO bound what they really mean is "There's a hot CPU | but it's across a network" ie: "I wrote really inefficient SQL | queries, therefor I'm IO bound, therefor I don't have to care | about CPU" - and the process pushes further and further | downstream as every service talking to one of these "IO bound" | services also becomes "IO bound". | crgwbr wrote: | This is obviously sometimes the case. But more often I've seen | IO bound apps spending all their time on network roundtrip | latency. I.E. not a few poorly performing SQL queries, but a | thousand queries which all take a millisecond or two. | kyuudou wrote: | So true about not coding for performance "because the disks are | slow". Almost all disk i/o, especially big-iron, has cache in | front of it. | | Maybe in the case of cloud storage - what does I/O bound mean | then? It should still conceivably be the same IMO. | brendangregg wrote: | Please stop using bonnie (I know, it's a 2008 post, but in case | it inspires anyone). It was useful at the time, but written in a | different era, and nowadays produces misleading results on multi- | threaded I/O stacks (along with other problems). I spoke to Tim | about this issue back at Sun, and he did write about it. | | Today I usually use fio for disk/FS benchmarks, as it's | frequently updated by Jens Axboe, who is also responsible for the | modern Linux multiqueue block I/O implementation. | zamadatix wrote: | (2008) ___________________________________________________________________ (page generated 2020-10-01 23:01 UTC)