From 791e480c6ac7a3e33adc5270b3fc99015f9f0c15 Mon Sep 17 00:00:00 2001 From: Brian Behlendorf Date: Mon, 13 Apr 2020 10:51:44 -0700 Subject: [PATCH] Disable user space reference tracking The memory and cpu cost of reference count tracking with the current implementation is significant. For this reason it has always been disabled by default for the kmods. Apply this same default to user space so ztest doesn't always incur this performance penalty. Our intention is to re-enable this by default for ztest once the code has been optimized. Since we expect to at some point provide a FUSE implementation we wouldn't want this enabled by default for libzpool. Reviewed-by: Ryan Moeller Signed-off-by: Brian Behlendorf Closes #10189 --- module/zfs/refcount.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/module/zfs/refcount.c b/module/zfs/refcount.c index a612b2f40c..6c9c305eda 100644 --- a/module/zfs/refcount.c +++ b/module/zfs/refcount.c @@ -26,11 +26,12 @@ #include #include -#ifdef _KERNEL -int reference_tracking_enable = FALSE; /* runs out of memory too easily */ -#else -int reference_tracking_enable = TRUE; -#endif +/* + * Reference count tracking is disabled by default. It's memory requirements + * are reasonable, however as implemented it consumes a significant amount of + * cpu time. Until its performance is improved it should be manually enabled. + */ +int reference_tracking_enable = FALSE; int reference_history = 3; /* tunable */ #ifdef ZFS_DEBUG