Add ZFS compressed ARC stats to top(1)

Provides:
amount of compressed data
logical size of compressed data (how much it would have taken uncompressed)
compression ratio (logical size : total ARC size)
Overhead (space consumed for compression headers)

Example output:
ARC: 31G Total, 18G MFU, 9067M MRU, 2236K Anon, 615M Header, 2947M Other
     25G Compressed, 54G Uncompressed, 1.76:1 Ratio, 2265M Overhead

Reviewed by:	jpaetzel, smh, imp, jhb (previous version)
MFC after:	2 week
Relnotes:	yes
Sponsored by:	ScaleEngine Inc.
Differential Revision:	https://reviews.freebsd.org/D9829

1 files changed, 4 insertions, 0 deletions

diff --git a/contrib/top/top.c b/contrib/top/top.c
index c74c1d1aa595..cf2f5e7c6f3b 100644
--- a/contrib/top/top.c
+++ b/contrib/top/top.c
@@ -125,6 +125,7 @@ void (*d_procstates)() = i_procstates;
 void (*d_cpustates)() = i_cpustates;
 void (*d_memory)() = i_memory;
 void (*d_arc)() = i_arc;
+void (*d_carc)() = i_carc;
 void (*d_swap)() = i_swap;
 void (*d_message)() = i_message;
 void (*d_header)() = i_header;
@@ -658,6 +659,7 @@ restart:
 	/* display memory stats */
 	(*d_memory)(system_info.memory);
 	(*d_arc)(system_info.arc);
+	(*d_carc)(system_info.carc);
 
 	/* display swap stats */
 	(*d_swap)(system_info.swap);
@@ -724,6 +726,7 @@ restart:
 		    d_cpustates = u_cpustates;
 		    d_memory = u_memory;
 		    d_arc = u_arc;
+		    d_carc = u_carc;
 		    d_swap = u_swap;
 		    d_message = u_message;
 		    d_header = u_header;
@@ -1190,6 +1193,7 @@ reset_display()
     d_cpustates  = i_cpustates;
     d_memory     = i_memory;
     d_arc        = i_arc;
+    d_carc       = i_carc;
     d_swap       = i_swap;
     d_message	 = i_message;
     d_header	 = i_header;