-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 On 11/21/14 07:18, Andriy Gapon wrote: > On 13/10/2014 23:39, Xin LI wrote: >> Author: delphij Date: Mon Oct 13 20:39:51 2014 New Revision: >> 273060 URL: https://svnweb.freebsd.org/changeset/base/273060 >> >> Log: Use write_psize instead of write_asize when doing >> vdev_space_update. Without this change the accounting of L2ARC >> usage would be wrong and give 16EB free space because the number >> became negative and overflows. >> >> Obtained from: FreeNAS (issue #6239) > > First, a link to the issue would be more convenient for reviewers. > Here it is https://bugs.freenas.org/issues/6239 > > Then, I would like to see a technical explanation for this change. > I could not find any explanation here or in the FreeNAS issue or in > the FreeNAS commit. > > As far as I can see, all calls to vdev_space_update() in the ARC > code are passed l2hdr->b_asize or a sum of b_asize fields of > multiple buffers. Thus, I am really surprised with this change and > would like to see reasoning behind it.
Hmm I think you are right that my change doesn't make sense but I can't remember the details either and suggests there is some other issues that was covered up by this. It looks like that I was confused because the L2ARC clock hand advances by buf_p_sz (unrelated but it should really be called buf_a_size) and the way we calculate allocated L2ARC free. Cheers, - -- Xin LI <delp...@delphij.net> https://www.delphij.net/ FreeBSD - The Power to Serve! Live free or die -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0 iQIcBAEBCgAGBQJUb5/DAAoJEJW2GBstM+nsJ9QQAI1r3y0dcQNegsfF997C5Kx/ kbS8qG9gmlwHwYlt7Q4RWH8z+kpo4poSrTz3i/0JaLBM5GN3NYq4LqVDIvX0MF4N wY8y1Fv8u6HVoor7gM0YbCXsAG7KJXHP+vj8MlczFiHdyK6Rl0HAiifMPUM1ie2I LHhmzSCzYsp8SJ2w+ggnwZQjTfJH+nwbcEHc9+2ke7u7cgb/pRuRMX8CfP6B6zfM +kOszv4UIp0xa8wA4ER/Ic8NlD9f8f7767vDxa1sfvCJaIeIoTjGplqDhkMuGaCc EcGy1rDH5iSvrRi9JbwZCtasYupwNINfIuKRcBTMUtSZDPu9D/cQfC1/b3DOhX97 uJt8GLEbQL/EeSOuqQ5aSAVzC08B6sJyTxnZ2/hIM96WEGhHvUPyng5AQ9umvRV4 Es10kly/KBRcCq8MfqJkA9e4a2sEIhSZyPPs+kcnFiBfQmyXlrkQgHrgCufHUO9B V4m5wsa+snv3sJQfg3HyOavYFY51/Yi9fWAeVUKt/NAsQQaOGNrvNIb8OEZamUS8 3rujexBEaDEW9wHFt3mZiN9zzh7+ZslwvSMh+B/qsp6nnoDJ9I7QzkFNUxHzlWZg Cc7d1ezbQF3t36S8ixpUER8w2bXGfAgnURvJWf86vNXwrFEo9BHUh42mauw9kMbZ 01SCBCFFDqpIUry9GFDW =uPh8 -----END PGP SIGNATURE----- _______________________________________________ svn-src-head@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
