Date: Wed, 28 Mar 2007 12:16:53 +0200 From: Ivan Voras <ivoras@fer.hr> To: freebsd-current@freebsd.org Subject: Re: NFS write() calls lead to read() calls? Message-ID: <eudfat$g2m$1@sea.gmane.org> In-Reply-To: <7ad7ddd90703280238r5dd3f30ftc1641926ecdf44a8@mail.gmail.com> References: <7ad7ddd90703280238r5dd3f30ftc1641926ecdf44a8@mail.gmail.com>
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This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enigBFA75766647B18FBF604C509 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Ulrich Spoerlein wrote: > If I run the scp again, I can see X MB/s going out from HostA, 2*X > MB/s coming in on HostB and X MB/s out plus X MB/s in on HostC. What's > happening is, that HostB issues one NFS READ call for every WRITE > call. The traffic flows like this: >=20 > -----> -----> > A B C > <----- >=20 > The real weirdness comes into play, when I simply cp(1) from HostB > itself like this: >=20 > hostB # cp 500MB /net/share/ >=20 > I can do this over and over again, and _never_ get any noteworthy > amount of NFS READ calls, only WRITE. The network traffic is also, as > you would expect. Have you tested with a small C program or a script to see if it's the=20 rewriting that's causing reads or is it some weird artifact of scp? --------------enigBFA75766647B18FBF604C509 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.5 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFGCkCcldnAQVacBcgRAv96AJsHvLGyoNbrhPl3aH3Pc4HJ7XmaXgCdGCnb XDdTho8tei7BT84dJvVQrxM= =bXtr -----END PGP SIGNATURE----- --------------enigBFA75766647B18FBF604C509--
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