Hannes Reinecke Large block sizes for IO
Channel: SUSE Labs
Date: 02/08/2023

Currently the Linux I/O stack is bounded by the machine page size,
ie the largest single block which Linux can write is capped by
the machine page size (eg 4k on x86).
For modern storage systems this is becoming a bottleneck as
for larger devices more and more metadata will need to be stored
and maintained. And for high-performance I/O larger blocksizes
are preferred, as the main latency is spent on setting up the
command, not on the actual data transfer.
So for efficient I/O it would be good if Linux would be able
to do I/O with blocksizes larger than 4k.
In this presentation I'll be giving and overview of the challenges
in this approach, and present the latest results from discussions
upstream and from LSF/MM.
And, of course, I would like to discuss with the audience on how
these challenges can be overcome.