On Wed, Sep 15, 2021 at 04:39:21PM +0200, Thomas Monjalon wrote: > 15/09/2021 16:25, Bruce Richardson: > > On Wed, Sep 15, 2021 at 03:52:35PM +0200, Thomas Monjalon wrote: > > > Hi, > > > > > > I would like to discuss some issues in logging of hugepage lookup. > > > The issues to be discussed will be enumerated and numbered below. > > > I will take an example of an x86 machine with 2M and 1G pages. > > > I reserve only 2M pages: > > > > > > usertools/dpdk-hugepages.py -p 2M -r 80M > > > > > > If I start a DPDK application with --log-level info > > > the only message I read makes me think something is wrong: > > > > > > EAL: No available 1048576 kB hugepages reported > > > > > > 1/ Log level is too high. > > > > > > > Agreed. > > > > > If I start with EAL in debug level, I can see which page size is used: > > > > > > --log-level debug --log-level lib.eal:debug > > > > > > EAL: No available 1048576 kB hugepages reported > > > [...] > > > EAL: Detected memory type: socket_id:0 hugepage_sz:2097152 > > > > > > 2/ The positive message should be at the same level as the negative one. > > > > A bit uncertain about this, as I think it need not always be the case. I > > think the log messages should be assessed independently. > > Not sure what you mean. Which level for which message? >
I mean the positive and negative log messages. I would assess the positive log level independently of what the log level chosen for the negative one, rather than saying they should be at the same level. > > > 3/ The sizes are sometimes written in bytes, sometimes in kB. > > > It should be always the highest unit, including GB. > > > > > > When using the --in-memory mode, things are worst: > > > > > > EAL: No available 1048576 kB hugepages reported > > > EAL: In-memory mode enabled, hugepages of size 1073741824 bytes will be > > > allocated anonymously > > > EAL: No free 1048576 kB hugepages reported on node 0 > > > EAL: No available 1048576 kB hugepages reported > > > [...] > > > EAL: Detected memory type: socket_id:0 hugepage_sz:1073741824 > > > EAL: Detected memory type: socket_id:0 hugepage_sz:2097152 > > > > > > > Yes, things should be consistent, having highest units is nice-to-have. If > > everything is consistently reported in KB or MB it's probably fine. > > Fine but not nice :) > I'm looking to improve the user experience, so "1GB" is definitely easier > to read than "1048576 kB", not talking about "1073741824". > Yes, agreed. The one small advantage of always just reporting in kB is that it is the units used by the kernel in reporting the page sizes: $ ls /sys/kernel/mm/hugepages/ hugepages-1048576kB hugepages-2048kB /Bruce
