Re: [dm-devel] [PATCH v4 15/20] libmultipath: implement find_multipaths_timeout
On Wed, Apr 04, 2018 at 06:16:22PM +0200, Martin Wilck wrote:
> This makes the timeout for "find_multipaths smart" configurable.
> If the timeout has a negative value (default), it's applied only
> to "known" hardware which is either in the hwtable or in a "device" section in
> multipath.conf. For typical non-multipath hardware, which is not in the
> hwtable, a short timeout of 1s is used, so that boot delays caused by
> pointlessly waiting e.g. for SATA devices will be minimal.
>
> It's expected that a "reasonable" timeout value depends less on the storage
> hardware itself but on other properties of the data center such as network
> latencies or distances. find_multipaths_timeout is therefore just a "defaults"
> section setting.
>
This patch adds trailing whitespace, but otherwise,
Reviewed-by: Benjamin Marzinski
> Signed-off-by: Martin Wilck
> ---
> libmultipath/config.h | 1 +
> libmultipath/defaults.h| 2 ++
> libmultipath/dict.c| 6 ++
> libmultipath/propsel.c | 25 +
> libmultipath/propsel.h | 1 +
> libmultipath/structs.h | 1 +
> multipath/multipath.conf.5 | 18 ++
> 7 files changed, 54 insertions(+)
>
> diff --git a/libmultipath/config.h b/libmultipath/config.h
> index c71d972..6e69a37 100644
> --- a/libmultipath/config.h
> +++ b/libmultipath/config.h
> @@ -174,6 +174,7 @@ struct config {
> int remove_retries;
> int max_sectors_kb;
> int ghost_delay;
> + int find_multipaths_timeout;
> unsigned int version[3];
>
> char * multipath_dir;
> diff --git a/libmultipath/defaults.h b/libmultipath/defaults.h
> index 19ad2bf..d7b87b4 100644
> --- a/libmultipath/defaults.h
> +++ b/libmultipath/defaults.h
> @@ -41,6 +41,8 @@
> #define DEFAULT_DISABLE_CHANGED_WWIDS 1
> #define DEFAULT_MAX_SECTORS_KB MAX_SECTORS_KB_UNDEF
> #define DEFAULT_GHOST_DELAY GHOST_DELAY_OFF
> +#define DEFAULT_FIND_MULTIPATHS_TIMEOUT -10
> +#define DEFAULT_UNKNOWN_FIND_MULTIPATHS_TIMEOUT 1
>
> #define DEFAULT_CHECKINT 5
> #define MAX_CHECKINT(a) (a << 2)
> diff --git a/libmultipath/dict.c b/libmultipath/dict.c
> index e695fdc..4be808d 100644
> --- a/libmultipath/dict.c
> +++ b/libmultipath/dict.c
> @@ -485,6 +485,10 @@ declare_hw_snprint(max_sectors_kb, print_nonzero)
> declare_mp_handler(max_sectors_kb, set_int)
> declare_mp_snprint(max_sectors_kb, print_nonzero)
>
> +declare_def_handler(find_multipaths_timeout, set_int)
> +declare_def_snprint_defint(find_multipaths_timeout, print_int,
> +DEFAULT_FIND_MULTIPATHS_TIMEOUT)
> +
> static int
> def_config_dir_handler(struct config *conf, vector strvec)
> {
> @@ -1519,6 +1523,8 @@ init_keywords(vector keywords)
> install_keyword("remove_retries", &def_remove_retries_handler,
> &snprint_def_remove_retries);
> install_keyword("max_sectors_kb", &def_max_sectors_kb_handler,
> &snprint_def_max_sectors_kb);
> install_keyword("ghost_delay", &def_ghost_delay_handler,
> &snprint_def_ghost_delay);
> + install_keyword("find_multipaths_timeout",
> &def_find_multipaths_timeout_handler,
> + &snprint_def_find_multipaths_timeout);
> __deprecated install_keyword("default_selector", &def_selector_handler,
> NULL);
> __deprecated install_keyword("default_path_grouping_policy",
> &def_pgpolicy_handler, NULL);
> __deprecated install_keyword("default_uid_attribute",
> &def_uid_attribute_handler, NULL);
> diff --git a/libmultipath/propsel.c b/libmultipath/propsel.c
> index 93974a4..70fb997 100644
> --- a/libmultipath/propsel.c
> +++ b/libmultipath/propsel.c
> @@ -912,3 +912,28 @@ out:
> condlog(3, "%s: ghost_delay = %s %s", mp->alias, buff, origin);
> return 0;
> }
> +
> +int select_find_multipaths_timeout(struct config *conf, struct path *pp)
> +{
> + char *origin;
> +
> + pp_set_conf(find_multipaths_timeout);
> + pp_set_default(find_multipaths_timeout,
> +DEFAULT_FIND_MULTIPATHS_TIMEOUT);
> +out:
> + /*
> + * If configured value is negative, and this "unkown" hardware
> + * (no hwentry), use very small timeout to avoid delays.
> + */
> + if (pp->find_multipaths_timeout < 0) {
> + pp->find_multipaths_timeout = - pp->find_multipaths_timeout;
> + if (!pp->hwe) {
> + pp->find_multipaths_timeout =
> + DEFAULT_UNKNOWN_FIND_MULTIPATHS_TIMEOUT;
> + origin = "(default for unkown hardware)";
> + }
> + }
> + condlog(3, "%s: timeout for find_multipaths \"smart\" = %ds %s",
> + pp->dev, pp->find_multipaths_timeout, origin);
> + return 0;
> +}
> diff --git a/libmultipath/propsel.h b/libmultipath/propsel.h
> index 136f906..b6475d0 100644
> --- a/libmultipath/propsel.h
> +++ b/libmultipath/propsel.h
> @@ -8,6 +8,7 @@ int select_hwhandler (struct config *conf, struct multipath *
> mp);
> int sel
[dm-devel] [PATCH v4 15/20] libmultipath: implement find_multipaths_timeout
This makes the timeout for "find_multipaths smart" configurable.
If the timeout has a negative value (default), it's applied only
to "known" hardware which is either in the hwtable or in a "device" section in
multipath.conf. For typical non-multipath hardware, which is not in the
hwtable, a short timeout of 1s is used, so that boot delays caused by
pointlessly waiting e.g. for SATA devices will be minimal.
It's expected that a "reasonable" timeout value depends less on the storage
hardware itself but on other properties of the data center such as network
latencies or distances. find_multipaths_timeout is therefore just a "defaults"
section setting.
Signed-off-by: Martin Wilck
---
libmultipath/config.h | 1 +
libmultipath/defaults.h| 2 ++
libmultipath/dict.c| 6 ++
libmultipath/propsel.c | 25 +
libmultipath/propsel.h | 1 +
libmultipath/structs.h | 1 +
multipath/multipath.conf.5 | 18 ++
7 files changed, 54 insertions(+)
diff --git a/libmultipath/config.h b/libmultipath/config.h
index c71d972..6e69a37 100644
--- a/libmultipath/config.h
+++ b/libmultipath/config.h
@@ -174,6 +174,7 @@ struct config {
int remove_retries;
int max_sectors_kb;
int ghost_delay;
+ int find_multipaths_timeout;
unsigned int version[3];
char * multipath_dir;
diff --git a/libmultipath/defaults.h b/libmultipath/defaults.h
index 19ad2bf..d7b87b4 100644
--- a/libmultipath/defaults.h
+++ b/libmultipath/defaults.h
@@ -41,6 +41,8 @@
#define DEFAULT_DISABLE_CHANGED_WWIDS 1
#define DEFAULT_MAX_SECTORS_KB MAX_SECTORS_KB_UNDEF
#define DEFAULT_GHOST_DELAY GHOST_DELAY_OFF
+#define DEFAULT_FIND_MULTIPATHS_TIMEOUT -10
+#define DEFAULT_UNKNOWN_FIND_MULTIPATHS_TIMEOUT 1
#define DEFAULT_CHECKINT 5
#define MAX_CHECKINT(a)(a << 2)
diff --git a/libmultipath/dict.c b/libmultipath/dict.c
index e695fdc..4be808d 100644
--- a/libmultipath/dict.c
+++ b/libmultipath/dict.c
@@ -485,6 +485,10 @@ declare_hw_snprint(max_sectors_kb, print_nonzero)
declare_mp_handler(max_sectors_kb, set_int)
declare_mp_snprint(max_sectors_kb, print_nonzero)
+declare_def_handler(find_multipaths_timeout, set_int)
+declare_def_snprint_defint(find_multipaths_timeout, print_int,
+ DEFAULT_FIND_MULTIPATHS_TIMEOUT)
+
static int
def_config_dir_handler(struct config *conf, vector strvec)
{
@@ -1519,6 +1523,8 @@ init_keywords(vector keywords)
install_keyword("remove_retries", &def_remove_retries_handler,
&snprint_def_remove_retries);
install_keyword("max_sectors_kb", &def_max_sectors_kb_handler,
&snprint_def_max_sectors_kb);
install_keyword("ghost_delay", &def_ghost_delay_handler,
&snprint_def_ghost_delay);
+ install_keyword("find_multipaths_timeout",
&def_find_multipaths_timeout_handler,
+ &snprint_def_find_multipaths_timeout);
__deprecated install_keyword("default_selector", &def_selector_handler,
NULL);
__deprecated install_keyword("default_path_grouping_policy",
&def_pgpolicy_handler, NULL);
__deprecated install_keyword("default_uid_attribute",
&def_uid_attribute_handler, NULL);
diff --git a/libmultipath/propsel.c b/libmultipath/propsel.c
index 93974a4..70fb997 100644
--- a/libmultipath/propsel.c
+++ b/libmultipath/propsel.c
@@ -912,3 +912,28 @@ out:
condlog(3, "%s: ghost_delay = %s %s", mp->alias, buff, origin);
return 0;
}
+
+int select_find_multipaths_timeout(struct config *conf, struct path *pp)
+{
+ char *origin;
+
+ pp_set_conf(find_multipaths_timeout);
+ pp_set_default(find_multipaths_timeout,
+ DEFAULT_FIND_MULTIPATHS_TIMEOUT);
+out:
+ /*
+* If configured value is negative, and this "unkown" hardware
+* (no hwentry), use very small timeout to avoid delays.
+*/
+ if (pp->find_multipaths_timeout < 0) {
+ pp->find_multipaths_timeout = - pp->find_multipaths_timeout;
+ if (!pp->hwe) {
+ pp->find_multipaths_timeout =
+ DEFAULT_UNKNOWN_FIND_MULTIPATHS_TIMEOUT;
+ origin = "(default for unkown hardware)";
+ }
+ }
+ condlog(3, "%s: timeout for find_multipaths \"smart\" = %ds %s",
+ pp->dev, pp->find_multipaths_timeout, origin);
+ return 0;
+}
diff --git a/libmultipath/propsel.h b/libmultipath/propsel.h
index 136f906..b6475d0 100644
--- a/libmultipath/propsel.h
+++ b/libmultipath/propsel.h
@@ -8,6 +8,7 @@ int select_hwhandler (struct config *conf, struct multipath *
mp);
int select_checker(struct config *conf, struct path *pp);
int select_getuid (struct config *conf, struct path * pp);
int select_prio (struct config *conf, struct path * pp);
+int select_find_multipaths_timeout(struct config *conf, struct path * pp);
int select_no_path_retry(struct config *conf, struct multipath *m
