[Bug 8512] rsync is slower than cp -- Reduce overhead to cp for transfer of large files

[samba-bugs at samba.org]

https://bugzilla.samba.org/show_bug.cgi?id=8512

--- Comment #5 from Peter van Hooft <hooft at natlab.research.philips.com> 2014-09-09 07:49:13 UTC ---
We use rsync to copy data from one file server to another using NFS3 mounts
over a 10Gb link. We found that upping the buffer sizes (as a quick test)
increases performance. When using --sparse this increases performance with a
factor of fifty, from 2MBps to 100MBps.
% diff -u rsync.h-org rsync.h
--- rsync.h-org 2014-04-13 19:36:59.000000000 +0200
+++ rsync.h     2014-09-08 16:20:41.427973852 +0200
@@ -131,11 +131,11 @@

 #define RSYNC_PORT 873

-#define SPARSE_WRITE_SIZE (1024)
-#define WRITE_SIZE (32*1024)
-#define CHUNK_SIZE (32*1024)
+#define SPARSE_WRITE_SIZE (128*1024)
+#define WRITE_SIZE (128*1024)
+#define CHUNK_SIZE (128*1024)
 #define MAX_MAP_SIZE (256*1024)
-#define IO_BUFFER_SIZE (32*1024)
+#define IO_BUFFER_SIZE (128*1024)
 #define MAX_BLOCK_SIZE ((int32)1 << 17)

 /* For compatibility with older rsyncs */
% 

It sure would be nice if these sizes were `officially' increased.

-- 
Configure bugmail: https://bugzilla.samba.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the QA contact for the bug.