Date: Sun, 19 May 2019 16:11:41 +0000 From: bugzilla-noreply@freebsd.org To: bugs@FreeBSD.org Subject: [Bug 219216] sched_bind() blocks if the entropy pool is starved Message-ID: <bug-219216-227-r9NtMNEKVr@https.bugs.freebsd.org/bugzilla/> In-Reply-To: <bug-219216-227@https.bugs.freebsd.org/bugzilla/> References: <bug-219216-227@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D219216 --- Comment #10 from Conrad Meyer <cem@freebsd.org> --- rand_harvestq has had CPU reduced significantly in 12.x timeframe =E2=80=94= previously it was attempting to obtain far more entropy and far more often than it actually needed. This was in part due to conservative estimates (r338293) = and in part due to bugs in random read (r338292, r339492). r287023, r334450 may also be relevant. If you have a concurrent reader, rand_harvestq will fight it for the global Fortuna state mutex on head today (and spin while waiting). You are somewh= at saved by READ_RANDOM_UIO dropping the Fortuna lock every 4kB (PAGE_SIZE). I have a revision proposed to reduce this conflict further: https://people.freebsd.org/~cem/rand_harvestq.png https://reviews.freebsd.org/D20313 --=20 You are receiving this mail because: You are the assignee for the bug.=
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