Re: PATCH [NFSd] NFSv3/TCP

[Greg Banks <gnb@melbourne.sgi.com>]

Neil Brown wrote:
> 
> There was once a patch floating around which allowed a larger
> NFSSVC_MAXBLKSIZE on architectures with large page sizes, but it never
> got properly submitted I think.

Then please consider this a resend.  I'll appreciate any guidance
about proper submission.

This patch has been in SGI's ProPack kernel for 6 months and resulted
in a significant improvement in NFS throughput at a number of customer
sites.

--- /usr/tmp/TmpDir.16250-0/linux/linux/include/linux/nfsd/const.h_1.5	Fri May  7
17:20:22 2004
+++ /usr/tmp/TmpDir.16250-0/linux/linux/include/linux/nfsd/const.h	Fri May  7
17:20:22 2004
@@ -12,6 +12,7 @@
 #include <linux/nfs.h>
 #include <linux/nfs2.h>
 #include <linux/nfs3.h>
+#include <asm/page.h>
 
 /*
  * Maximum protocol version supported by knfsd
@@ -19,9 +20,16 @@
 #define NFSSVC_MAXVERS		3
 
 /*
- * Maximum blocksize supported by daemon currently at 8K
+ * Maximum blocksize supported by daemon.  We want the largest
+ * value which 1) fits in a UDP datagram less some headers
+ * 2) is a multiple of page size 3) can be successfully kmalloc()ed
+ * by each nfsd.   
  */
-#define NFSSVC_MAXBLKSIZE	(8*1024)
+#if PAGE_SIZE > (16*1024)
+#define NFSSVC_MAXBLKSIZE	(32*1024)
+#else
+#define NFSSVC_MAXBLKSIZE	(2*PAGE_SIZE)
+#endif
 
 #ifdef __KERNEL__
 


Greg.
-- 
Greg Banks, R&D Software Engineer, SGI Australian Software Group.
I don't speak for SGI.