Hi, We are working on iSCSI server and Fibre channel target for Linux based servers and we noticed that the SLES8 kernel (even the latest 2.4.21-266) is showing extemely high CPU usage for TCP receive only (i.e iSCSI writes from client). With kernel profile enabled it appears that skb_copy_bits is consuming lots of cpu (80 - 100%). The iSCSI reads from client does not show high cpu usage and delivers 112MB/sec easily even with MTU 1500 and no special tuning of e1000. The same software Mayastor does NOT show high cpu usage for Redhat Enterprise linux both on read and writes. Looks as though some patch is missing? SLES8 2.4.21-266 SR1330 platform, xeon 2.2 dual, Intel e1000 driver Mayastor iscsi server
From the client we have to run bonnie++ over the iscsi disk.
Thanks in advance. -SK -- Build cost-effective open Storage Area Network over Fibre Channel or iSCSI using Mayastor. Download disk server at http://www.pavitrasoft.com