[PATCH v2 2/2] NFSv4.2: mount overhead should not be used as threshold for inter-server copy

From: Dai Ngo <dai.ngo@oracle.com>
To: olga.kornievskaia@gmail.com
Cc: linux-nfs@vger.kernel.org, trondmy@hammerspace.com,
	bfields@fieldses.org, chuck.lever@oracle.com
Subject: [PATCH v2 2/2] NFSv4.2: mount overhead should not be used as threshold for inter-server copy
Date: Fri,  2 Apr 2021 19:30:31 -0400	[thread overview]
Message-ID: <20210402233031.36731-3-dai.ngo@oracle.com> (raw)
In-Reply-To: <20210402233031.36731-1-dai.ngo@oracle.com>

Since mount and unmount are not done on each copy request, its overhead
should not be considered as the threshold for doing inter-server copy.
The threshold used to determine sync or async copy is also used to decide
whether copy is done with inter-server copy or generic copy.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
---
 fs/nfs/nfs4file.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/fs/nfs/nfs4file.c b/fs/nfs/nfs4file.c
index 441a2fa073c8..67ca798a1a79 100644
--- a/fs/nfs/nfs4file.c
+++ b/fs/nfs/nfs4file.c
@@ -158,13 +158,11 @@ static ssize_t __nfs4_copy_file_range(struct file *file_in, loff_t pos_in,
 		sync = true;
 retry:
 	if (!nfs42_files_from_same_server(file_in, file_out)) {
-		/* for inter copy, if copy size if smaller than 12 RPC
-		 * payloads, fallback to traditional copy. There are
-		 * 14 RPCs during an NFSv4.x mount between source/dest
-		 * servers.
+		/*
+		 * for inter copy, if copy size is small enough
+		 * for sync copy then fallback to traditional copy.
 		 */
-		if (sync ||
-			count <= 14 * NFS_SERVER(file_inode(file_in))->rsize)
+		if (sync)
 			return -EOPNOTSUPP;
 		cn_resp = kzalloc(sizeof(struct nfs42_copy_notify_res),
 				GFP_NOFS);
-- 
2.9.5

