Attachment 7893 Details for Bug 9161 – git-am fix for 4.0.0.

[patch] git-am fix for 4.0.0.

0001-Sigh-.-Removing-optimization-prematurely-is-the-root.patch (text/plain), 2.51 KB, created by Jeremy Allison on 2012-09-13 19:56:43 UTC

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Creator: Jeremy Allison

Created: 2012-09-13 19:56:43 UTC

Size: 2.51 KB

patch

obsolete

>From 56b752512597acaffa94a979ef9140760e0f5cf3 Mon Sep 17 00:00:00 2001
>From: Jeremy Allison <jra@samba.org>
>Date: Thu, 13 Sep 2012 10:13:21 -0700
>Subject: [PATCH] Sigh :-(. Removing optimization prematurely is the root of
> all evil :-(.
>
>Sorry for the mistake, but the LastDir singleton cache in vfs_ChDir()
>actually plays an important role. When we're processing a stream of
>SMB1/SMB2/SMB3 requests we don't want to add a chdir()/getcwd()
>system call pair on every request if they're all on the same connection
>and dealing with the same base path.
>
>I did some testing with a program that times 1,000,000 chdir()
>requests vs. 1,000,000 strcmp requests and it's a penalty of 10x
>doing the system calls.
>
>Just because it's old code, doesn't mean it's bad :-(.
>
>Autobuild-User(master): Jeremy Allison <jra@samba.org>
>Autobuild-Date(master): Thu Sep 13 21:31:42 CEST 2012 on sn-devel-104
>---
> source3/smbd/globals.c |    1 +
> source3/smbd/globals.h |    1 +
> source3/smbd/vfs.c     |   13 +++++++++++++
> 3 files changed, 15 insertions(+), 0 deletions(-)
>
>diff --git a/source3/smbd/globals.c b/source3/smbd/globals.c
>index 874f35d..80f6a66 100644
>--- a/source3/smbd/globals.c
>+++ b/source3/smbd/globals.c
>@@ -85,6 +85,7 @@ int conn_ctx_stack_ndx = 0;
> 
> struct vfs_init_function_entry *backends = NULL;
> char *sparse_buf = NULL;
>+char *LastDir = NULL;
> 
> struct smbd_parent_context *am_parent = NULL;
> struct memcache *smbd_memcache_ctx = NULL;
>diff --git a/source3/smbd/globals.h b/source3/smbd/globals.h
>index 1cefe51..566f04d 100644
>--- a/source3/smbd/globals.h
>+++ b/source3/smbd/globals.h
>@@ -101,6 +101,7 @@ extern int conn_ctx_stack_ndx;
> struct vfs_init_function_entry;
> extern struct vfs_init_function_entry *backends;
> extern char *sparse_buf;
>+extern char *LastDir;
> 
> struct smbd_parent_context;
> extern struct smbd_parent_context *am_parent;
>diff --git a/source3/smbd/vfs.c b/source3/smbd/vfs.c
>index 7d19440..fe99ee2 100644
>--- a/source3/smbd/vfs.c
>+++ b/source3/smbd/vfs.c
>@@ -801,14 +801,27 @@ int vfs_ChDir(connection_struct *conn, const char *path)
> {
> 	int ret;
> 
>+	if (!LastDir) {
>+		LastDir = SMB_STRDUP("");
>+	}
>+
> 	if (strcsequal(path,".")) {
> 		return 0;
> 	}
> 
>+	if (*path == '/' && strcsequal(LastDir,path)) {
>+		return 0;
>+	}
>+
> 	DEBUG(4,("vfs_ChDir to %s\n",path));
> 
> 	ret = SMB_VFS_CHDIR(conn,path);
> 	if (ret == 0) {
>+		/* Global cache. */
>+		SAFE_FREE(LastDir);
>+		LastDir = SMB_STRDUP(path);
>+
>+		/* conn cache. */
> 		TALLOC_FREE(conn->cwd);
> 		conn->cwd = vfs_GetWd(conn, conn);
> 		DEBUG(4,("vfs_ChDir got %s\n",conn->cwd));
>-- 
>1.7.7.3
>

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Attachments on bug 9161: 7893