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--7AUc2qLy4jB3hD7Z Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Sep 18, 2005 at 02:12:05PM +1200, Nikolai Schupbach wrote: > Hello, >=20 > We have installed FreeBSD 4.11 with SMP enabled in our kernel on a dual I= ntel > Xeon 3.2 EMT64 server. We have found file operations like untaring the po= rts > tree, or copying directories with many files extremely slow. However if we > disable SMP support and run on a single CPU the performance is fast. >=20 > Using iostat the performance to untar ports tree is around 4Mb/sec with a= n SMP > kernel. Without SMP iostat reports around 50Mb/sec. >=20 > Is this normal for 4.11? We tired SMP on 5.4 and it did not suffer from t= his > problem, but we had to revert to 4.11 for other performance reasons. >=20 > Are we better off to run without SMP? As is well known, SMP support on FreeBSD 4.x was rudimentary, and performance is poor when two processes are both performing tasks that require entering the kernel. This has been a major focus of development in the FreeBSD 5 branch and beyond, so if SMP performance is important to you you definitely want the latest release (or wait for the forthcoming FreeBSD 6.0). Kris --7AUc2qLy4jB3hD7Z Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (FreeBSD) iD8DBQFDLbmuWry0BWjoQKURAqRHAKDQt34S8QYethYvZWjyANr6q0lWygCeISjN RrF2uw7T3MKud7RvR3z1lhw= =0Gtv -----END PGP SIGNATURE----- --7AUc2qLy4jB3hD7Z--