Linux 6.4 Device Mapper To See Improved Concurrent I/O Performance

[phoronix]

Phoronix: Linux 6.4 Device Mapper To See Improved Concurrent I/O Performance

Thanks to forthcoming work out of Red Hat, the Linux 6.4 Device Mapper (DM) code is expected to see some optimization work that can significantly benefit concurrent I/O performance... In one case at least acquiring buffers now about 25 times faster...

https://www.phoronix.com/news/Linux-6.4-DM-Concurrent-IO

[Anux]

I never noticed any perf impact from a DM device but 25x sounds not bad. Are we talking about LVM, Softraid and the like?

[Vorpal]

I never noticed any perf impact from a DM device but 25x sounds not bad. Are we talking about LVM, Softraid and the like?

It is 25x for a specific part of an operation. That does not translate to 25x read speed, write speed or anything else that is a meaningful benchmark.

Most likely it would be a few percent on any real world benchmark at most. Maybe a bit more on a very directed synthentic benchmark. Only by profiling that specific function would you see a 25x improvement.

See also Amdahl's law

[guglovich]

I wish this would help BTRFS...

[mathieu.cossette]

Oh yeah! Linux FTW! Years of hard work from developers and programmers all around the world is beginning to show awesome improvements!

[pipe13]

I wish this would help BTRFS...

Yeah dat. But we'll settle for Stratis...

[Joe2021]

It is 25x for a specific part of an operation. That does not translate to 25x read speed, write speed or anything else that is a meaningful benchmark.

Yes, most likely it won't result in more speed, but in less CPU load for the same task.

[Anux]

It is 25x for a specific part of an operation. That does not translate to 25x read speed, write speed or anything else that is a meaningful benchmark.

Ofcoure it says in the article:
> benefit concurrent I/O performance... In one case at least acquiring buffers now about 25 times faster.
And since my desktop is mostly sequential ... it might help in my server but my storage devices and network will limit things. That's why I wrote "not noticed perf impact", even raid 6 + luks is limited by network (1Gb/s).