On Jan 30, 2008 5:34 PM, James Bottomley <James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote: > > On Wed, 2008-01-30 at 09:38 +0100, Bart Van Assche wrote: > > On Jan 30, 2008 12:32 AM, FUJITA Tomonori <fujita.tomonori@xxxxxxxxxxxxx> wrote: > > > > > > iSER has parameters to limit the maximum size of RDMA (it needs to > > > repeat RDMA with a poor configuration)? > > > > Please specify which parameters you are referring to. As you know I > > had already repeated my tests with ridiculously high values for the > > following iSER parameters: FirstBurstLength, MaxBurstLength and > > MaxRecvDataSegmentLength (16 MB, which is more than the 1 MB block > > size specified to dd). > > the 1Mb block size is a bit of a red herring. Unless you've > specifically increased the max_sector_size and are using an sg_chain > converted driver, on x86 the maximum possible transfer accumulation is > 0.5MB. I did not publish the results, but I have also done tests with other block sizes. The other sizes I tested were between 0.1MB and 10MB. The performance difference for these other sizes compared to a block size of 1MB was small (smaller than the variance between individual tests results). Bart. - To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
