On 7/01/2010 10:44 AM, Dmitri Girski wrote:
Hi everybody, Many thanks to everyone replied, I think we are on the right way. I've used tcpdump to generate the logs and there are a lot of dropped packets due to the bad checksum. Network guy is currently looking at the problem and most likely this is hardware issue.
Hang on a sec. You need to ignore bad checksums on *outbound* packets, because many (most?) Ethernet drivers implement some level of TCP offloading, and this will result in packet sniffers seeing invalid checksums for transmitted packets - the checksums haven't been generated by the NIC yet.
Unless you know for sure that your NIC doesn't do TSO, ignore bad checksums on outbound packets from the local interface.
-- Craig Ringer -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
