Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
/ 2006-04-03 02:28:48 -0500 \ Maurice Volaski: > Web100 is a patch to the Linux kernel (see http://www.web100.org) that enables one to get statistics on all TCP traffic. There was a bug > in the previous posted version, 2.5.8, but the author seems to have fixed it. > > So as far I can tell, all network traffic works except for drbd! > > The computer running drbd (0.7.17 under kernel 126.96.36.199) has web100 and displays this message when it should be receiving data from its > peer (the acting primary): > > <3>[14938.140724] drbd1: [drbd1_receiver/8822] sock_sendmsg time expired, ko = 4294967295 this message is triggered when we have data blocks pending but made no progress in sending them for longer than the configured "drbd-ping" intervall, which defaults to six seconds, iirc. the "knock out counter" is then decremented with each drbd-ping packet sent. in case a drbd-ping packet is not answered in time, we declare "network failure" and try to reconnect. in case the ping packet is answered, we continue to ping untill the ko-count reaches zero, in which case we declare the peer's io-subsystem broken, and go StandAlone. in case we make some progress (just one data block is enough) we reset the ko-count. > (Interestingly, the peer won't let me access the drbd disks; they appear hung) > > The author is not convinced web100 is responsible. He believes it is > possible that web100 alters timing that somehow could be triggering a > bug elsewhere in the kernel, including in drbd. so this is not a bug in drbd, but web100 alters the timing "somehow" that it takes several seconds to get one single data block through. this is also what makes your disks appear hung: they are as slow as the network connection now, which seems to be throttled by web100 (or your configuration of web100) down to a couple of bytes every few seconds... -- : Lars Ellenberg Tel +43-1-8178292-0 : : LINBIT Information Technologies GmbH Fax +43-1-8178292-82 : : Schoenbrunner Str. 244, A-1120 Vienna/Europe http://www.linbit.com : __ please use the "List-Reply" function of your email client.