From dbf03959244c392073281c10badd2095397ad2f2 Mon Sep 17 00:00:00 2001 From: Andrew Tridgell Date: Fri, 29 Oct 2004 07:29:26 +0000 Subject: r3357: removed the need to use TDB_CLEAR_IF_FIRST in Samba4. We found a few months ago that TDB_CLEAR_IF_FIRST is extremely inefficient for large numbers of connections, due to a fundamental limitation in the way posix byte range locking is implemented. Rather than the nasty workaround we had for Samba3, we now have a single "cleanup tmp files" function that runs when smbd starts. That deletes the tmp tdbs, so TDB_CLEAR_IF_FIRST is not needed at all. (This used to be commit ffa285bc783c775a2d53a58fb691ca339e6c76ae) --- source4/lib/util.c | 15 +++++++++------ source4/libcli/unexpected.c | 2 +- source4/ntvfs/common/brlock.c | 2 +- source4/ntvfs/common/opendb.c | 2 +- source4/smbd/rewrite.c | 16 ++++------------ source4/smbd/service.c | 30 ++++++++++++++++++++++++++++++ 6 files changed, 46 insertions(+), 21 deletions(-) diff --git a/source4/lib/util.c b/source4/lib/util.c index d7c5661f7d..8b27bf070c 100644 --- a/source4/lib/util.c +++ b/source4/lib/util.c @@ -705,15 +705,18 @@ char *name_to_fqdn(TALLOC_CTX *mem_ctx, const char *name) char *lock_path(TALLOC_CTX* mem_ctx, const char *name) { - char *fname; + char *fname, *dname; - fname = talloc_strdup(mem_ctx, lp_lockdir()); - trim_string(fname,"","/"); + dname = talloc_strdup(mem_ctx, lp_lockdir()); + trim_string(dname,"","/"); - if (!directory_exist(fname,NULL)) - mkdir(fname,0755); + if (!directory_exist(dname,NULL)) { + mkdir(dname,0755); + } - fname = talloc_asprintf(mem_ctx, "%s/%s", fname, name); + fname = talloc_asprintf(mem_ctx, "%s/%s", dname, name); + + talloc_free(dname); return fname; } diff --git a/source4/libcli/unexpected.c b/source4/libcli/unexpected.c index e109c9d5bf..19a02bdeb8 100644 --- a/source4/libcli/unexpected.c +++ b/source4/libcli/unexpected.c @@ -50,7 +50,7 @@ void unexpected_packet(struct packet_struct *p) mem_ctx = talloc_init("receive_unexpected"); if (!mem_ctx) return; tdbd = tdb_wrap_open(NULL, lock_path(mem_ctx, "unexpected.tdb"), 0, - TDB_CLEAR_IF_FIRST|TDB_DEFAULT, + TDB_DEFAULT, O_RDWR | O_CREAT, 0644); talloc_destroy(mem_ctx); if (!tdbd) { diff --git a/source4/ntvfs/common/brlock.c b/source4/ntvfs/common/brlock.c index b43f0705a5..0f6af3e971 100644 --- a/source4/ntvfs/common/brlock.c +++ b/source4/ntvfs/common/brlock.c @@ -84,7 +84,7 @@ struct brl_context *brl_init(TALLOC_CTX *mem_ctx, servid_t server, uint16_t tid, path = lock_path(brl, "brlock.tdb"); brl->w = tdb_wrap_open(brl, path, 0, - TDB_DEFAULT|TDB_CLEAR_IF_FIRST, + TDB_DEFAULT, O_RDWR|O_CREAT, 0600); talloc_free(path); if (brl->w == NULL) { diff --git a/source4/ntvfs/common/opendb.c b/source4/ntvfs/common/opendb.c index d8ca4c999d..a66549b764 100644 --- a/source4/ntvfs/common/opendb.c +++ b/source4/ntvfs/common/opendb.c @@ -88,7 +88,7 @@ struct odb_context *odb_init(TALLOC_CTX *mem_ctx, servid_t server, uint16_t tid, path = lock_path(odb, "openfiles.tdb"); odb->w = tdb_wrap_open(odb, path, 0, - TDB_DEFAULT|TDB_CLEAR_IF_FIRST, + TDB_DEFAULT, O_RDWR|O_CREAT, 0600); talloc_free(path); if (odb->w == NULL) { diff --git a/source4/smbd/rewrite.c b/source4/smbd/rewrite.c index 035532a01f..ff311c6680 100644 --- a/source4/smbd/rewrite.c +++ b/source4/smbd/rewrite.c @@ -19,18 +19,12 @@ BOOL share_access_check(struct smbsrv_request *req, struct smbsrv_tcon *tcon, in { return True; } /* - * initialize an smb process + * initialize an smb process. Guaranteed to be called only once per + * smbd instance (so it can assume it is starting from scratch, and + * delete temporary files etc) */ void smbd_process_init(void) { - TALLOC_CTX *mem_ctx; - - mem_ctx = talloc_init("smbd_process_init talloc"); - if (!mem_ctx) { - DEBUG(0,("smbd_process_init: ERROR: No memory\n")); - exit(1); - } - /* possibly reload the services file. */ reload_services(NULL, True); @@ -39,9 +33,7 @@ void smbd_process_init(void) DEBUG(2,("Changed root to %s\n", lp_rootdir())); } - /* Start old-style secrets subsystem */ - - talloc_destroy(mem_ctx); + service_cleanup_tmp_files(); } void init_subsystems(void) diff --git a/source4/smbd/service.c b/source4/smbd/service.c index ca5f5e7531..33c0d5fcbd 100644 --- a/source4/smbd/service.c +++ b/source4/smbd/service.c @@ -349,3 +349,33 @@ void service_close_listening_sockets(struct server_context *srv_ctx) } } } + + +/* + cleanup temporary files. This is the new alternative to + TDB_CLEAR_IF_FIRST. Unfortunately TDB_CLEAR_IF_FIRST is not + efficient on unix systems due to the lack of scaling of the byte + range locking system. So instead of putting the burden on tdb to + cleanup tmp files, this function deletes them. You need to expand + the list here as appropriate. +*/ +void service_cleanup_tmp_files(void) +{ + const char *list[] = { + "openfiles.tdb", + "brlock.tdb", + "unexpected.tdb"}; + int i; + for (i=0;i