Date: Sun, 6 Jul 2014 15:33:59 +0300 From: Konstantin Belousov <kostikbel@gmail.com> To: Stefan Parvu <sparvu@systemdatarecorder.org> Cc: freebsd-hackers@freebsd.org Subject: Re: run-queue length question Message-ID: <20140706123359.GD93733@kib.kiev.ua> In-Reply-To: <20140706143212.3d22d0adfa5dece52de203a3@systemdatarecorder.org> References: <20140706143212.3d22d0adfa5dece52de203a3@systemdatarecorder.org>
next in thread | previous in thread | raw e-mail | index | archive | help
--aq8B+PobjgurrfqM Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Jul 06, 2014 at 02:32:12PM +0300, Stefan Parvu wrote: > Hi, >=20 > Im trying to understand what FreeBSD kernel counts for run-queue length.= =20 >=20 > Traditional we count as queue length: number of processes which are runni= ng plus=20 > the number that are runnable (waiting to execute) - we *dont* count proce= sses waiting=20 > for storage, network etc.=20 >=20 > Linux kernel has added into run-queue length the iowait processes which m= akes > load average values big and disproportionate to the reality for example d= uring=20 > disk io tests. >=20 > How does FreeBSD handle this part ? Is the queue length simple the number= of=20 > running processes + waiting to run or not as we used to have in UNIX worl= d ? It is the Linux which follows the traditional definition of the load, by counting running, ready to run and 'blocked on the fast i/o' processes as adding to the load average. Also, I remember that FreeBSD up to 4.x followed this definition. Sometime during the 5.x rewrites the load was redefined to only count running + ready to run threads, which is the current definition, used by LA. --aq8B+PobjgurrfqM Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIcBAEBAgAGBQJTuUI3AAoJEJDCuSvBvK1BBTAP/2rodsb979Wc3jEbC2zDxHXN WOa9thboYfLf7JRaicBS9ydyO0NPtHhg4B2GDhBdbQ4DYUwPaBqa+EGuyuhhVR4V YaPUzWt8wxezX24H2+VkZiJxfL/tMmo+EEHYEFPPlsfZSc/IGL1csCwLASjYrqZ0 dSRSaF5Omm/wmt3MNUIgIQgCtL5Ik++f7RxkvuTuyNS8p1SYLWa/3/RefMJwywkX fO76q8HgRdm3Q9DYqCOFxvlaapnVpNWNa4YvJg82BUz0T+l01jjly5xt8CuPJ+MW YVKJPE04lnr4pzQTVjqHPAqY6juFoz/KWx+qfbM9XBhLvjLss+S22zWIGOIiywzT C00uDh16jUrddrQ5Rfk27JhBtR83L9+5LacOpTFgxu5q4YoZ8m0DXSHjAVmBHDCL 9wb+dDIbPOT/HNIkT4wQ9YNrgdl4deoE+yF9XIhH+Zlh+RkPHkLa1Csdh3+1gbrE EzstgI8r3kiHct/WZgvPkkOSDrgtncxnHzYucN9/ATBFHNccKYlMtjqtceTBgib3 R0VUZXBe8WYEUBeiUfA6HT8RwtcN9eqvjNN5hMc6yHZ9aTkx38AALw6RvXnApQk3 RF4C4kp05j0FhhEdOjaI7BbnNSoGpFEtl1fNX2tL0Vq4bbrcp700ebro4DW8uBAV kogQIcJJx7t5vLxY3ust =wU+P -----END PGP SIGNATURE----- --aq8B+PobjgurrfqM--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20140706123359.GD93733>