[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

[Xen-devel] Live migration: "netbuf race" messages can cause significant perfomance impact


Someone found that doing a live migration of a domain that had ballooned down took far longer to migrate. (Ballooned down from 3000M to 1000M, 31 seconds vs 89 seconds, real time) I came up with a complex theory and asked him to look in the xend.log to confirm it. He didn't, but he mentioned there was a lot of "netbuf race" messages in the log. In this particular case, live migration generated approximately 512000 "netbuf race" messages. Deleting the DPRINTF reduced the migration time to 11 seconds.

While it is simple enough to submit a patch to delete this DPRINTF, perhaps something more subtle is called for such as modifying the migrate/save command paths to accept a debug argument and passing to xc_save?


John Byrne

Xen-devel mailing list



Lists.xenproject.org is hosted with RackSpace, monitoring our
servers 24x7x365 and backed by RackSpace's Fanatical Support®.