Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
Hello, This is basically a repeat of: http://lists.linbit.com/pipermail/drbd-user/2011-August/016758.html 32GB RAM, Debian Squeeze, 3.2 (debian backport) kernel, 8.3.12 DRBD, IPOIB in connected mode with a 64k MTU. Just 2 DRBD resources. After encountering this for the first time (never showed up in two weeks of stress testing, which only goes to prove that real life just can't be simulated) I found the above article and changed the following sysctls: vm/min_free_kbytes = 262144 net.core.rmem_max = 16777216 net.core.wmem_max = 16777216 net.ipv4.tcp_rmem = 65536 87380 16777216 net.ipv4.tcp_wmem = 65536 65536 16777216 net/ipv4/tcp_mem is by default at "775464 1033954 1550928" which should be plentiful. After the changes I disconnected and reconnected the resources, thus hopefully applying those changes to the actual links. And initially I couldn't reproduce the problem, but it showed up again last night. Lars hinted at "atomic reserves" in his reply, which particular parameters are we talking about here? See this for the pertinent kernel log entry in my case: http://pastebin.com/hTJuCYDX Regards, Christian -- Christian Balzer Network/Systems Engineer chibi at gol.com Global OnLine Japan/Fusion Communications http://www.gol.com/