opensm SA DB dump/restore: added option to load SA DB once

PATCH Superseded Yevgeny Kliteynik 2 participants 5 messages Nov 4, 2009 – Dec 13, 2009 2 messages not in the archive InfiniBand

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Yevgeny Kliteynik

author

2009-11-04 11:00 UTC #0 lore raw

PATCH v2 1/3 opensm SA DB dump/restore: added option to load SA DB once

Added option to load SA DB once: 'sa_db_load_once'. This will cause OSM to load SA DB once during first master heavy sweep, and then OSM will move to the usual SA mode.

The option is not exposed through OSM command line, but only through options file.

[v2 - no changes, just rebased and resolved conflicts]

Signed-off-by Yevgeny Kliteynik <[email protected]>

---
 opensm/include/opensm/osm_subnet.h |    5 +++++
 opensm/opensm/osm_sa.c             |   20 +++++++++++++++++++-
 opensm/opensm/osm_subnet.c         |    7 +++++++
 3 files changed, 31 insertions(+), 1 deletions(-)

opensm/include/opensm/osm_subnet.h +5 -0

index 0302f91..871a833 100644
@@ -200,6 +200,7 @@ typedef struct osm_subn_opt {
 	char *ids_guid_file;
 	char *guid_routing_order_file;
 	char *sa_db_file;
+	boolean_t sa_db_load_once;
 	boolean_t do_mesh_analysis;
 	boolean_t exit_on_fatal;
 	boolean_t honor_guid2lid_file;

@@ -411,6 +412,10 @@ typedef struct osm_subn_opt {
 *	sa_db_file
 *		Name of the SA database file.
 *
+*	sa_db_load_once
+*		When TRUE causes sa_db_file to be loaded only at the
+*		first master sweep.
+*
 *	exit_on_fatal
 *		If TRUE (default) - SM will exit on fatal subnet initialization
 *		issues.

opensm/opensm/osm_sa.c +19 -1

index 2db8ba2..e44eab4 100644
@@ -912,6 +912,12 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		return 0;
 	}
 
+	if (p_osm->subn.opt.sa_db_load_once && !p_osm->subn.first_time_master_sweep) {
+		OSM_LOG(&p_osm->log, OSM_LOG_VERBOSE,
+			"Not first sweep - skip SA DB restore\n");
+		return 0;
+	}
+
 	file = fopen(file_name, "r");
 	if (!file) {
 		OSM_LOG(&p_osm->log, OSM_LOG_ERROR | OSM_LOG_SYS, "ERR 4C02: "

@@ -920,6 +926,10 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		return -1;
 	}
 
+	OSM_LOG(&p_osm->log, OSM_LOG_VERBOSE,
+		"Restoring SA DB from file \'%s\'\n",
+		file_name);
+
 	lineno = 0;
 
 	while (fgets(line, sizeof(line) - 1, file) != NULL) {

@@ -1096,7 +1106,15 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		}
 	}
 
-	if (!rereg_clients)
+	/*
+	 * If restoring SA DB is required only once, SM should go
+	 * into the usual mode right after that, which means that
+	 * client re-registration should be required even after
+	 * the restore - there is a chance that OSM died right after
+	 * some MCMember joined MCast group, and his membership
+	 * didn't make it into the SA DB file.
+	 */
+	if (!p_osm->subn.opt.sa_db_load_once && !rereg_clients)
 		p_osm->subn.opt.no_clients_rereg = TRUE;
 
 _error:

opensm/opensm/osm_subnet.c +7 -0

index cac5e94..b0ffddd 100644
@@ -348,6 +348,7 @@ static const opt_rec_t opt_tbl[] = {
 	{ "ids_guid_file", OPT_OFFSET(ids_guid_file), opts_parse_charp, NULL, 0 },
 	{ "guid_routing_order_file", OPT_OFFSET(guid_routing_order_file), opts_parse_charp, NULL, 0 },
 	{ "sa_db_file", OPT_OFFSET(sa_db_file), opts_parse_charp, NULL, 0 },
+	{ "sa_db_load_once", OPT_OFFSET(sa_db_load_once), opts_parse_boolean, NULL, 1 },
 	{ "do_mesh_analysis", OPT_OFFSET(do_mesh_analysis), opts_parse_boolean, NULL, 1 },
 	{ "exit_on_fatal", OPT_OFFSET(exit_on_fatal), opts_parse_boolean, NULL, 1 },
 	{ "honor_guid2lid_file", OPT_OFFSET(honor_guid2lid_file), opts_parse_boolean, NULL, 1 },

@@ -746,6 +747,7 @@ void osm_subn_set_default_opt(IN osm_subn_opt_t * p_opt)
 	p_opt->ids_guid_file = NULL;
 	p_opt->guid_routing_order_file = NULL;
 	p_opt->sa_db_file = NULL;
+	p_opt->sa_db_load_once = FALSE;
 	p_opt->do_mesh_analysis = FALSE;
 	p_opt->exit_on_fatal = TRUE;
 	p_opt->enable_quirks = FALSE;

@@ -1446,6 +1448,11 @@ int osm_subn_output_conf(FILE *out, IN osm_subn_opt_t * p_opts)
 		p_opts->sa_db_file ? p_opts->sa_db_file : null_str);
 
 	fprintf(out,
+		"# If TRUE causes SA database to be loaded only at\n"
+		"# the first master sweep\nsa_db_load_once %s\n\n",
+		p_opts->sa_db_load_once ? "TRUE" : "FALSE");
+
+	fprintf(out,
 		"#\n# HANDOVER - MULTIPLE SMs OPTIONS\n#\n"
 		"# SM priority used for deciding who is the master\n"
 		"# Range goes from 0 (lowest priority) to 15 (highest).\n"

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A message that is not in the archive (sent off-list or not yet received): 4AF15EBD.6010307-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org

Sasha Khapyorsky

2009-11-26 13:30 UTC #2 lore raw

Hi Yevgeny,

Quoted 3 lines · Yevgeny Kliteynik

Added option to load SA DB once: 'sa_db_load_once'. This will cause OSM to load SA DB once during first master heavy sweep, and then OSM will move to the usual SA mode.

It is probably should be done by default, without any options. I don't think that loading SA DB on an every sweep is anyhow in use today.

Quoted 4 lines

The option is not exposed through OSM command line, but only through options file.
[v2 - no changes, just rebased and resolved conflicts]

Please next time place commit message unrelated lines under '---' and before diffstat output, in this way git am skips this during applying.

Quoted 64 lines

Signed-off-by Yevgeny Kliteynik <[email protected]>

---
 opensm/include/opensm/osm_subnet.h |    5 +++++
 opensm/opensm/osm_sa.c             |   20 +++++++++++++++++++-
 opensm/opensm/osm_subnet.c         |    7 +++++++
 3 files changed, 31 insertions(+), 1 deletions(-)

opensm/include/opensm/osm_subnet.h +5 -0

index 0302f91..871a833 100644
@@ -200,6 +200,7 @@ typedef struct osm_subn_opt {
 	char *ids_guid_file;
 	char *guid_routing_order_file;
 	char *sa_db_file;
+	boolean_t sa_db_load_once;
 	boolean_t do_mesh_analysis;
 	boolean_t exit_on_fatal;
 	boolean_t honor_guid2lid_file;

@@ -411,6 +412,10 @@ typedef struct osm_subn_opt {
 *	sa_db_file
 *		Name of the SA database file.
 *
+*	sa_db_load_once
+*		When TRUE causes sa_db_file to be loaded only at the
+*		first master sweep.
+*
 *	exit_on_fatal
 *		If TRUE (default) - SM will exit on fatal subnet initialization
 *		issues.

opensm/opensm/osm_sa.c +10 -1

index 2db8ba2..e44eab4 100644
@@ -912,6 +912,12 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		return 0;
 	}
 
+	if (p_osm->subn.opt.sa_db_load_once && !p_osm->subn.first_time_master_sweep) {
+		OSM_LOG(&p_osm->log, OSM_LOG_VERBOSE,
+			"Not first sweep - skip SA DB restore\n");
+		return 0;
+	}
+
 	file = fopen(file_name, "r");
 	if (!file) {
 		OSM_LOG(&p_osm->log, OSM_LOG_ERROR | OSM_LOG_SYS, "ERR 4C02: "

@@ -920,6 +926,10 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		return -1;
 	}
 
+	OSM_LOG(&p_osm->log, OSM_LOG_VERBOSE,
+		"Restoring SA DB from file \'%s\'\n",
+		file_name);
+
 	lineno = 0;
 
 	while (fgets(line, sizeof(line) - 1, file) != NULL) {

@@ -1096,7 +1106,15 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		}
 	}
 
-	if (!rereg_clients)

opensm/opensm/osm_sa.c int osm_sa_db_file_load(osm_opensm_t * p_osm) · line 1118

Quoted 10 lines

opensm/opensm/osm_sa.c +9 -0

+	/*
+	 * If restoring SA DB is required only once, SM should go
+	 * into the usual mode right after that, which means that
+	 * client re-registration should be required even after
+	 * the restore - there is a chance that OSM died right after
+	 * some MCMember joined MCast group, and his membership
+	 * didn't make it into the SA DB file.
+	 */
+	if (!p_osm->subn.opt.sa_db_load_once && !rereg_clients)
 		p_osm->subn.opt.no_clients_rereg = TRUE;

Hmm, if you are going to request clients reregistration unconditionally then what is the reason to restore SA DB?

Maybe you wanted to switch this flag off *after* first sweep, but I'm not sure following your comment.

Sasha

Quoted 43 lines

opensm/opensm/osm_sa.c +0 -0

 _error:

opensm/opensm/osm_subnet.c +7 -0

index cac5e94..b0ffddd 100644
@@ -348,6 +348,7 @@ static const opt_rec_t opt_tbl[] = {
 	{ "ids_guid_file", OPT_OFFSET(ids_guid_file), opts_parse_charp, NULL, 0 },
 	{ "guid_routing_order_file", OPT_OFFSET(guid_routing_order_file), opts_parse_charp, NULL, 0 },
 	{ "sa_db_file", OPT_OFFSET(sa_db_file), opts_parse_charp, NULL, 0 },
+	{ "sa_db_load_once", OPT_OFFSET(sa_db_load_once), opts_parse_boolean, NULL, 1 },
 	{ "do_mesh_analysis", OPT_OFFSET(do_mesh_analysis), opts_parse_boolean, NULL, 1 },
 	{ "exit_on_fatal", OPT_OFFSET(exit_on_fatal), opts_parse_boolean, NULL, 1 },
 	{ "honor_guid2lid_file", OPT_OFFSET(honor_guid2lid_file), opts_parse_boolean, NULL, 1 },

@@ -746,6 +747,7 @@ void osm_subn_set_default_opt(IN osm_subn_opt_t * p_opt)
 	p_opt->ids_guid_file = NULL;
 	p_opt->guid_routing_order_file = NULL;
 	p_opt->sa_db_file = NULL;
+	p_opt->sa_db_load_once = FALSE;
 	p_opt->do_mesh_analysis = FALSE;
 	p_opt->exit_on_fatal = TRUE;
 	p_opt->enable_quirks = FALSE;

@@ -1446,6 +1448,11 @@ int osm_subn_output_conf(FILE *out, IN osm_subn_opt_t * p_opts)
 		p_opts->sa_db_file ? p_opts->sa_db_file : null_str);
 
 	fprintf(out,
+		"# If TRUE causes SA database to be loaded only at\n"
+		"# the first master sweep\nsa_db_load_once %s\n\n",
+		p_opts->sa_db_load_once ? "TRUE" : "FALSE");
+
+	fprintf(out,
 		"#\n# HANDOVER - MULTIPLE SMs OPTIONS\n#\n"
 		"# SM priority used for deciding who is the master\n"
 		"# Range goes from 0 (lowest priority) to 15 (highest).\n"

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Yevgeny Kliteynik

author

2009-12-06 10:32 UTC #3 lore raw

Hi Sasha,

Quoted 9 lines · Sasha Khapyorsky

Hi Yevgeny,
Quoted 3 lines · Yevgeny Kliteynik
Added option to load SA DB once: 'sa_db_load_once'. This will cause OSM to load SA DB once during first master heavy sweep, and then OSM will move to the usual SA mode.
It is probably should be done by default, without any options. I don't think that loading SA DB on an every sweep is anyhow in use today.

OK, didn't want to change current behavior in case anyone uses it, but no problem changing it to default behavior. No need for a separate option.

Quoted 7 lines

Quoted 4 lines
The option is not exposed through OSM command line, but only through options file.
[v2 - no changes, just rebased and resolved conflicts]
Please next time place commit message unrelated lines under '---' and before diffstat output, in this way git am skips this during applying.

Quoted 77 lines

Quoted 63 lines

Signed-off-by Yevgeny Kliteynik <[email protected]>

---
 opensm/include/opensm/osm_subnet.h |    5 +++++
 opensm/opensm/osm_sa.c             |   20 +++++++++++++++++++-
 opensm/opensm/osm_subnet.c         |    7 +++++++
 3 files changed, 31 insertions(+), 1 deletions(-)

opensm/include/opensm/osm_subnet.h +5 -0

index 0302f91..871a833 100644
@@ -200,6 +200,7 @@ typedef struct osm_subn_opt {
 	char *ids_guid_file;
 	char *guid_routing_order_file;
 	char *sa_db_file;
+	boolean_t sa_db_load_once;
 	boolean_t do_mesh_analysis;
 	boolean_t exit_on_fatal;
 	boolean_t honor_guid2lid_file;

@@ -411,6 +412,10 @@ typedef struct osm_subn_opt {
 *	sa_db_file
 *		Name of the SA database file.
 *
+*	sa_db_load_once
+*		When TRUE causes sa_db_file to be loaded only at the
+*		first master sweep.
+*
 *	exit_on_fatal
 *		If TRUE (default) - SM will exit on fatal subnet initialization
 *		issues.

opensm/opensm/osm_sa.c +10 -1

index 2db8ba2..e44eab4 100644
@@ -912,6 +912,12 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		return 0;
 	}
 
+	if (p_osm->subn.opt.sa_db_load_once && !p_osm->subn.first_time_master_sweep) {
+		OSM_LOG(&p_osm->log, OSM_LOG_VERBOSE,
+			"Not first sweep - skip SA DB restore\n");
+		return 0;
+	}
+
 	file = fopen(file_name, "r");
 	if (!file) {
 		OSM_LOG(&p_osm->log, OSM_LOG_ERROR | OSM_LOG_SYS, "ERR 4C02: "

@@ -920,6 +926,10 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		return -1;
 	}
 
+	OSM_LOG(&p_osm->log, OSM_LOG_VERBOSE,
+		"Restoring SA DB from file \'%s\'\n",
+		file_name);
+
 	lineno = 0;
 
 	while (fgets(line, sizeof(line) - 1, file) != NULL) {

@@ -1096,7 +1106,15 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		}
 	}
 
-	if (!rereg_clients)

opensm/opensm/osm_sa.c int osm_sa_db_file_load(osm_opensm_t * p_osm) · line 1118

Quoted 10 lines

opensm/opensm/osm_sa.c +9 -0

+	/*
+	 * If restoring SA DB is required only once, SM should go
+	 * into the usual mode right after that, which means that
+	 * client re-registration should be required even after
+	 * the restore - there is a chance that OSM died right after
+	 * some MCMember joined MCast group, and his membership
+	 * didn't make it into the SA DB file.
+	 */
+	if (!p_osm->subn.opt.sa_db_load_once && !rereg_clients)
 		p_osm->subn.opt.no_clients_rereg = TRUE;

Hmm, if you are going to request clients reregistration unconditionally then what is the reason to restore SA DB?

Quoted 2 lines

Maybe you wanted to switch this flag off *after* first sweep, but I'm not sure following your comment.

We have a dump file with mcast members, and OSM is loading this file. Suppose OSM has successfully loaded the whole file. But this does not mean that there's no need to request client re-registration on all the hosts. Consider the following case:
- Heavy sweep - SM dumps current SA DB to a file
- Client asks to join some mcast group
- SM gets the request and processes it
- The request is OK - SM sets the 'dirty' flag and responds to client
- Client gets the response
- SM dies
- SM is restarted - it loads the existing SA DB, which does not includes the latest client's membership
- Loading of the whole SA DB is OK - no client re-register request is issued
- Client remains disconnected from the mcast group

I want to be able to tell SM to request client re-register after loading the SA DB even if all was OK.

So there are 3 options to do it:

1. Completely rely on 'no_clients_rereg' option only. Do not alter this option, doesn't matter if the SA DB reloading succeeded or not.

2. Combine 'no_clients_rereg' option with loading SA DB
result: if loading succeeded, do whatever 'no_clients_rereg' option says. If loading failed at some point, turn off the 'no_clients_rereg' option (turn on re-registartion requests, don't you just love the double-negative logic?)

3. Add new option for this particular case.

I'm all for option 2, and this is what I'm implementing in V3 series patches.

Thoughts?

-- Yevgeny

Quoted 40 lines

Sasha

Quoted 37 lines

opensm/opensm/osm_sa.c +0 -0

 _error:

opensm/opensm/osm_subnet.c +7 -0

index cac5e94..b0ffddd 100644
@@ -348,6 +348,7 @@ static const opt_rec_t opt_tbl[] = {
 	{ "ids_guid_file", OPT_OFFSET(ids_guid_file), opts_parse_charp, NULL, 0 },
 	{ "guid_routing_order_file", OPT_OFFSET(guid_routing_order_file), opts_parse_charp, NULL, 0 },
 	{ "sa_db_file", OPT_OFFSET(sa_db_file), opts_parse_charp, NULL, 0 },
+	{ "sa_db_load_once", OPT_OFFSET(sa_db_load_once), opts_parse_boolean, NULL, 1 },
 	{ "do_mesh_analysis", OPT_OFFSET(do_mesh_analysis), opts_parse_boolean, NULL, 1 },
 	{ "exit_on_fatal", OPT_OFFSET(exit_on_fatal), opts_parse_boolean, NULL, 1 },
 	{ "honor_guid2lid_file", OPT_OFFSET(honor_guid2lid_file), opts_parse_boolean, NULL, 1 },

@@ -746,6 +747,7 @@ void osm_subn_set_default_opt(IN osm_subn_opt_t * p_opt)
 	p_opt->ids_guid_file = NULL;
 	p_opt->guid_routing_order_file = NULL;
 	p_opt->sa_db_file = NULL;
+	p_opt->sa_db_load_once = FALSE;
 	p_opt->do_mesh_analysis = FALSE;
 	p_opt->exit_on_fatal = TRUE;
 	p_opt->enable_quirks = FALSE;

@@ -1446,6 +1448,11 @@ int osm_subn_output_conf(FILE *out, IN osm_subn_opt_t * p_opts)
 		p_opts->sa_db_file ? p_opts->sa_db_file : null_str);
 
 	fprintf(out,
+		"# If TRUE causes SA database to be loaded only at\n"
+		"# the first master sweep\nsa_db_load_once %s\n\n",
+		p_opts->sa_db_load_once ? "TRUE" : "FALSE");
+
+	fprintf(out,
 		"#\n# HANDOVER - MULTIPLE SMs OPTIONS\n#\n"
 		"# SM priority used for deciding who is the master\n"
 		"# Range goes from 0 (lowest priority) to 15 (highest).\n"

Signature · 1 line

1.5.1.4

Quoted 6 lines

Quoted 5 lines
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A message that is not in the archive (sent off-list or not yet received): 4B1B883D.3080508-LDSdmyG8hGV8YrgS2mwiifqBs+8SCbDb@public.gmane.org

Sasha Khapyorsky

2009-12-13 16:23 UTC #5 lore raw

Quoted 22 lines · Yevgeny Kliteynik

Quoted 19 lines
Quoted 5 lines
opensm/opensm/osm_sa.c +0 -1
@@ -1096,7 +1106,15 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
 		}
 	}
 
-	if (!rereg_clients)
opensm/opensm/osm_sa.c int osm_sa_db_file_load(osm_opensm_t * p_osm) · line 1118
Quoted 10 lines
opensm/opensm/osm_sa.c +9 -0
+	/*
+	 * If restoring SA DB is required only once, SM should go
+	 * into the usual mode right after that, which means that
+	 * client re-registration should be required even after
+	 * the restore - there is a chance that OSM died right after
+	 * some MCMember joined MCast group, and his membership
+	 * didn't make it into the SA DB file.
+	 */
+	if (!p_osm->subn.opt.sa_db_load_once && !rereg_clients)
 		p_osm->subn.opt.no_clients_rereg = TRUE;
Hmm, if you are going to request clients reregistration unconditionally then what is the reason to restore SA DB?
Quoted 2 lines
Maybe you wanted to switch this flag off *after* first sweep, but I'm not sure following your comment.

Quoted 16 lines

We have a dump file with mcast members, and OSM is loading this file. Suppose OSM has successfully loaded the whole file. But this does not mean that there's no need to request client re-registration on all the hosts. Consider the following case:
- Heavy sweep - SM dumps current SA DB to a file
- Client asks to join some mcast group
- SM gets the request and processes it
- The request is OK - SM sets the 'dirty' flag and responds to client
- Client gets the response
- SM dies
- SM is restarted - it loads the existing SA DB, which does not includes the latest client's membership
- Loading of the whole SA DB is OK - no client re-register request is issued
- Client remains disconnected from the mcast group

It is easy to think about such or similar scenarios. But OTOH if you are going to request clients reregistration, why to preload SA DB?

Quoted 2 lines

I want to be able to tell SM to request client re-register after loading the SA DB even if all was OK.

So my question is when preloading SA DB buys something for us when clients will reregister anyway? Bugs?

Quoted 12 lines

So there are 3 options to do it:
1. Completely rely on 'no_clients_rereg' option only. Do not alter this option, doesn't matter if the SA DB reloading succeeded or not.
2. Combine 'no_clients_rereg' option with loading SA DB
result: if loading succeeded, do whatever 'no_clients_rereg' option says. If loading failed at some point, turn off the 'no_clients_rereg' option (turn on re-registartion requests, don't you just love the double-negative logic?)

Quoted 4 lines

3. Add new option for this particular case.
I'm all for option 2, and this is what I'm implementing in V3 series patches.

IMHO this is better than what was proposed in the original patch. Think that we can make it this way.

Sasha
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Yevgeny Kliteynik

author

2009-12-13 21:38 UTC #6 lore raw

Quoted 40 lines · Sasha Khapyorsky

Quoted 22 lines · Yevgeny Kliteynik
Quoted 19 lines
Quoted 5 lines
opensm/opensm/osm_sa.c +0 -1
@@ -1096,7 +1106,15 @@ int osm_sa_db_file_load(osm_opensm_t * p_osm)
  		}
  	}
 
-	if (!rereg_clients)
opensm/opensm/osm_sa.c int osm_sa_db_file_load(osm_opensm_t * p_osm) · line 1118
Quoted 10 lines
opensm/opensm/osm_sa.c +9 -0
+	/*
+	 * If restoring SA DB is required only once, SM should go
+	 * into the usual mode right after that, which means that
+	 * client re-registration should be required even after
+	 * the restore - there is a chance that OSM died right after
+	 * some MCMember joined MCast group, and his membership
+	 * didn't make it into the SA DB file.
+	 */
+	if (!p_osm->subn.opt.sa_db_load_once&&  !rereg_clients)
  		p_osm->subn.opt.no_clients_rereg = TRUE;
Hmm, if you are going to request clients reregistration unconditionally then what is the reason to restore SA DB?
Quoted 2 lines
Maybe you wanted to switch this flag off *after* first sweep, but I'm not sure following your comment.
Quoted 16 lines
We have a dump file with mcast members, and OSM is loading this file. Suppose OSM has successfully loaded the whole file. But this does not mean that there's no need to request client re-registration on all the hosts. Consider the following case:
- Heavy sweep - SM dumps current SA DB to a file
- Client asks to join some mcast group
- SM gets the request and processes it
- The request is OK - SM sets the 'dirty' flag and responds to client
- Client gets the response
- SM dies
- SM is restarted - it loads the existing SA DB, which does not includes the latest client's membership
- Loading of the whole SA DB is OK - no client re-register request is issued
- Client remains disconnected from the mcast group

Quoted 8 lines

It is easy to think about such or similar scenarios. But OTOH if you are going to request clients reregistration, why to preload SA DB?
Quoted 2 lines
I want to be able to tell SM to request client re-register after loading the SA DB even if all was OK.
So my question is when preloading SA DB buys something for us when clients will reregister anyway? Bugs?

Well, I wouldn't call it "bugs". It's more of non-compliant application behavior. Many applications just not able to survive things like MLID change - they are not listening to events and do not request mcast group re-registration.

-- Yevgeny

Quoted 14 lines

Quoted 14 lines
So there are 3 options to do it:
1. Completely rely on 'no_clients_rereg' option only. Do not alter this option, doesn't matter if the SA DB reloading succeeded or not.
2. Combine 'no_clients_rereg' option with loading SA DB
result: if loading succeeded, do whatever 'no_clients_rereg' option says. If loading failed at some point, turn off the 'no_clients_rereg' option (turn on re-registartion requests, don't you just love the double-negative logic?)
3. Add new option for this particular case.

Quoted 8 lines

Quoted 2 lines
I'm all for option 2, and this is what I'm implementing in V3 series patches.
IMHO this is better than what was proposed in the original patch. Think that we can make it this way.
Sasha

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