Note: "permalinks" may not be as permanent as we would like,
direct links of old sources may well be a few messages off.
On Tuesday 22 July 2008 10:54:32 am Lars Ellenberg wrote: > > > do you use tcp checksum offloading? > > > any other tcp offloading? <snip> > ethtool -k ethX "ethtool -k eth2" output is as follows: Offload parameters for eth2: Cannot get device udp large send offload settings: Operation not supported Cannot get device generic segmentation offload settings: Operation not supported rx-checksumming: on tx-checksumming: on scatter-gather: on tcp segmentation offload: on udp fragmentation offload: off generic segmentation offload: off So it looks like we are using some offloading, and that it's possible to adjust these settings via ethtool. > the better "end-to-end" your checksums are, > the more likely they will detect transfer errors. > > so we have that data-integrity-alg in drbd, which puts a > drbd-to-drbd checksum on the data Thanks for the clear and detailed explanation. Do I understand correctly that using data-integrity-alg at the drbd layer is still the most reliable checksum, regardless of tcp offloading? In other words, is there any reason to adjust offloading settings if data-integrity-alg is enabled? Also, do I understand correctly that failing hash values cause a packet (or block?) to be invisibly re-sent? Or is some other action required in the event that a hash comparison fails? Thank you, Jeffrey