Hi, Try to add flow for traffic you want to get prioritized, I noticed that opensolaris tends to drop network connectivity without priority flows defined, I believe this is a feature presented by crossbow itself. flowadm is your friend that is. I found this particularly annoying if you monitor servers with icmp-ping and high load causes checks to fail therefore triggering unnecessary alarms.
Yours Markus Kovero -----Original Message----- From: zfs-discuss-boun...@opensolaris.org [mailto:zfs-discuss-boun...@opensolaris.org] On Behalf Of Saso Kiselkov Sent: 28. joulukuuta 2009 15:25 To: zfs-discuss@opensolaris.org Subject: Re: [zfs-discuss] ZFS write bursts cause short app stalls -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I progressed with testing a bit further and found that I was hitting another scheduling bottleneck - the network. While the write burst was running and ZFS was commiting data to disk, the server was dropping incomming UDP packets ("netstat -s | grep udpInOverflows" grew by about 1000-2000 packets during every write burst). To work around that I had to boost the scheduling priority of recorder processes to the real-time class and I also had to lower zfs_txg_timeout=1 (there was still minor packet drop after just doing priocntl on the processes) to even out the CPU load. Any ideas on why ZFS should completely thrash the network layer and make it drop incomming packets? Regards, - -- Saso Robert Milkowski wrote: > On 26/12/2009 12:22, Saso Kiselkov wrote: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA1 >> >> Thank you, the post you mentioned helped me move a bit forward. I tried >> putting: >> >> zfs:zfs_txg_timeout = 1 > btw: you can tune it on a live system without a need to do reboots. > > mi...@r600:~# echo zfs_txg_timeout/D | mdb -k > zfs_txg_timeout: > zfs_txg_timeout:30 > mi...@r600:~# echo zfs_txg_timeout/W0t1 | mdb -kw > zfs_txg_timeout:0x1e = 0x1 > mi...@r600:~# echo zfs_txg_timeout/D | mdb -k > zfs_txg_timeout: > zfs_txg_timeout:1 > mi...@r600:~# echo zfs_txg_timeout/W0t30 | mdb -kw > zfs_txg_timeout:0x1 = 0x1e > mi...@r600:~# echo zfs_txg_timeout/D | mdb -k > zfs_txg_timeout: > zfs_txg_timeout:30 > mi...@r600:~# > -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.9 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iEYEARECAAYFAks4sa8ACgkQRO8UcfzpOHAASgCdF1QWcKvpvK58BPBVr9EDmrWK zmoAoLeX3Q+avIDbb+CONlh++pAIGOob =NcRo -----END PGP SIGNATURE----- _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
