On Thu, Nov 26, 2020 at 12:28:16PM +0100, Paul Menzel wrote: > [No idea, if I should carbon copy the list or not.]
I hope you don't mind, but I've CC'd the list in replying. At this point it's helpful for others to see: 1. jio compiled and worked 2. jio didn't crash or rm -Rf / your system 3. what kind of information it produced > > Am 26.11.20 um 04:02 schrieb Vito Caputo: > > Hello systemd-devel, > > > > Recent discussion here about journal space consumption happened to > > occur while I was exploring use of the new io_uring linux kernel > > interface in combination with journal files. > > > > What began as a curiosity about this new kernel interface, and what it > > would be like to program journal file processing with some kind of > > continuation-passing style C code bolted onto it, evolved into > > something already providing new visibility into journal-file space > > utilization not AFAIK currently offered by systemd's journalctl (not > > that it couldn't be added there too). > > > > I've called this program jio, pronounced "jai-oh". > > Thank you for writing and sharing this. > You're welcome, it was fun to write. Thanks for being a guinea pig! > > At this time jio implements three basic functions: > > > > 1. `jio report usage` > > > > READ-ONLY > > > > Measures and reports space actually used by objects in all > > accessible journal files, classified by object type. > > > > > > 2. `jio report tail-waste` > > > > READ-ONLY > > > > Measures and reports unused space allocated to the tail ends of > > all journal files, classified by journal state. Journal state > > being Online, Offline, or Archived. > > Thank you. It builds fine on Debian Sid/unstable with GCC 10.2.0-19 (some > warnings), and the results are attached. > Any chance you could mail me the warnings? I see none here, would prefer a clean build for others. <snip> > Per-object-type usage: > UNUSED: [0] 0.00 B > Data: [2404148] 261.85 MiB > Field: [6491] 331.51 KiB > Entry: [1521426] 712.38 MiB > DataHashTable: [100] 355.56 MiB > FieldHashTable: [100] 521.88 KiB > EntryArray: [554339] 577.14 MiB > Tag: [0] 0.00 B > Aggregate object usage: 1.86 GiB of 2.22 GiB spanning 100 journal files > <snip> > > Totals: > Tail-waste by state: > Offline [3]: 7.23 MiB, 2% of all tail-waste > Online [1]: 7.37 MiB, 2% of all tail-waste > Archived [96]: 339.82 MiB, 95% of all tail-waste > > Aggregate tail-waste: 354.42 MiB, 15% of 2.22 GiB spanning 100 journal > files This is useful information. On my system there's an accumulation of Offline user journals accounting for a majority of the tail-waste, which being Offline the `jio reclaim tail-waste` won't touch. We need more samples from the field, but this suggests it might be something unique to my system. Thanks again! _______________________________________________ systemd-devel mailing list systemd-devel@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/systemd-devel
