When doing round-robin reads from a multi-plex volume, only switch to the

next plex if the sector to be read isn't nearby the last read sector.

Submitted by:  Vsevolod Lobko <seva@ip.net.ua> via ru@
Approved by:   grog (mentor)

1 files changed, 7 insertions, 0 deletions

diff --git a/sys/dev/vinum/vinumvar.h b/sys/dev/vinum/vinumvar.h
index 807439c..8e7edd8 100644
--- a/sys/dev/vinum/vinumvar.h
+++ b/sys/dev/vinum/vinumvar.h
@@ -361,6 +361,13 @@ enum parityop {
     rebuildandcheckparity,				    /* rebuildparity with the -v option */
 };
 
+/*
+ * When doing round-robin reads from a multi-plex volume, switch to the
+ * next plex if the difference of the last read sector and the next sector
+ * to be read is this many sectors.
+ */
+#define ROUNDROBIN_SWITCH	128			    /* 64k */
+
 #ifdef VINUMDEBUG
 /* Debugging stuff */
 enum debugflags {