Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On 10/09/2018 04:21 PM, Wei Liu wrote:
> On Tue, Oct 09, 2018 at 04:16:48PM +0100, George Dunlap wrote:
>> On 10/09/2018 04:12 PM, Wei Liu wrote:
>>> On Tue, Oct 02, 2018 at 04:49:26PM +0100, George Dunlap wrote:
Commit 3b4adba ("tools/libxl: include scheduler parameters in the
output of xl list -l") added scheduling parameters to the set of
information collected by libxl_retrieve_domain_configuration(), in
order to report that information in `xl list -l`.
Unfortunately, libxl_retrieve_domain_configuration() is also called by
the migration / save code, and the results passed to the restore /
receive code. This meant scheduler parameters were inadvertently
added to the migration stream, without proper consideration for how to
handle corner cases. The result was that if migrating from a host
running one scheduler to a host running a different scheduler, the
migration would fail with an error like the following:
libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain 1:Getting
domain sched credit: Invalid argument
libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain 1:cannot
(re-)build domain: -3
Luckily there's a fairly straightforward way to set parameters in a
"best-effort" fashion. libxl provides a single struct containing the
parameters of all schedulers, as well as a parameter specifying which
scheduler. Parameters not used by a given scheduler are ignored.
Additionally, the struct contains a parameter to specify the
scheduler. If you specify a specific scheduler,
libxl_domain_sched_params_set() will fail if there's a different
scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will use
the value of the current scheduler for that domain.
In domcreate_stream_done(), before calling libxl__build_post(), set
the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
scheduler parameters from the previous instantiation on a best-effort
basis.
Signed-off-by: George Dunlap
---
CC: Ian Jackson
CC: Wei Liu
CC: Andrew Cooper
CC: Jan Beulich
CC: Dario Faggioli
CC: Juergen Gross
---
tools/libxl/libxl_create.c | 9 +
1 file changed, 9 insertions(+)
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index dcfde7787e..caf79d4620 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -1237,6 +1237,15 @@ static void domcreate_stream_done(libxl__egc *egc,
ret = ERROR_INVAL;
goto out;
}
+
+/*
+ * The scheduler on the sending domain may be different than the
+ * scheduler running here. Setting the scheduler to UNKNOWN will
+ * cause the code to take to take whatever parameters are
+ * available in that scheduler, while discarding the rest.
+ */
+info->sched_params.sched = LIBXL_SCHEDULER_UNKNOWN;
>>>
>>> But this function is called by normal domain creation as well. What if
>>> libxl user does set the parameter?
>>
>> Is it? I thought the `stream` meant it was only called when doing
>> migrate / resume.
>
> Yes, you're right. Feel free to add my ack.
Great, thanks. I'll re-push the credit2 default patch after this gets
pushed to master.
-George
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Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On Tue, Oct 09, 2018 at 04:16:48PM +0100, George Dunlap wrote:
> On 10/09/2018 04:12 PM, Wei Liu wrote:
> > On Tue, Oct 02, 2018 at 04:49:26PM +0100, George Dunlap wrote:
> >> Commit 3b4adba ("tools/libxl: include scheduler parameters in the
> >> output of xl list -l") added scheduling parameters to the set of
> >> information collected by libxl_retrieve_domain_configuration(), in
> >> order to report that information in `xl list -l`.
> >>
> >> Unfortunately, libxl_retrieve_domain_configuration() is also called by
> >> the migration / save code, and the results passed to the restore /
> >> receive code. This meant scheduler parameters were inadvertently
> >> added to the migration stream, without proper consideration for how to
> >> handle corner cases. The result was that if migrating from a host
> >> running one scheduler to a host running a different scheduler, the
> >> migration would fail with an error like the following:
> >>
> >> libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain 1:Getting
> >> domain sched credit: Invalid argument
> >> libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain 1:cannot
> >> (re-)build domain: -3
> >>
> >> Luckily there's a fairly straightforward way to set parameters in a
> >> "best-effort" fashion. libxl provides a single struct containing the
> >> parameters of all schedulers, as well as a parameter specifying which
> >> scheduler. Parameters not used by a given scheduler are ignored.
> >> Additionally, the struct contains a parameter to specify the
> >> scheduler. If you specify a specific scheduler,
> >> libxl_domain_sched_params_set() will fail if there's a different
> >> scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will use
> >> the value of the current scheduler for that domain.
> >>
> >> In domcreate_stream_done(), before calling libxl__build_post(), set
> >> the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
> >> scheduler parameters from the previous instantiation on a best-effort
> >> basis.
> >>
> >> Signed-off-by: George Dunlap
> >> ---
> >> CC: Ian Jackson
> >> CC: Wei Liu
> >> CC: Andrew Cooper
> >> CC: Jan Beulich
> >> CC: Dario Faggioli
> >> CC: Juergen Gross
> >> ---
> >> tools/libxl/libxl_create.c | 9 +
> >> 1 file changed, 9 insertions(+)
> >>
> >> diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
> >> index dcfde7787e..caf79d4620 100644
> >> --- a/tools/libxl/libxl_create.c
> >> +++ b/tools/libxl/libxl_create.c
> >> @@ -1237,6 +1237,15 @@ static void domcreate_stream_done(libxl__egc *egc,
> >> ret = ERROR_INVAL;
> >> goto out;
> >> }
> >> +
> >> +/*
> >> + * The scheduler on the sending domain may be different than the
> >> + * scheduler running here. Setting the scheduler to UNKNOWN will
> >> + * cause the code to take to take whatever parameters are
> >> + * available in that scheduler, while discarding the rest.
> >> + */
> >> +info->sched_params.sched = LIBXL_SCHEDULER_UNKNOWN;
> >
> > But this function is called by normal domain creation as well. What if
> > libxl user does set the parameter?
>
> Is it? I thought the `stream` meant it was only called when doing
> migrate / resume.
Yes, you're right. Feel free to add my ack.
Wei.
>
> -George
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Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On 10/09/2018 04:12 PM, Wei Liu wrote:
> On Tue, Oct 02, 2018 at 04:49:26PM +0100, George Dunlap wrote:
>> Commit 3b4adba ("tools/libxl: include scheduler parameters in the
>> output of xl list -l") added scheduling parameters to the set of
>> information collected by libxl_retrieve_domain_configuration(), in
>> order to report that information in `xl list -l`.
>>
>> Unfortunately, libxl_retrieve_domain_configuration() is also called by
>> the migration / save code, and the results passed to the restore /
>> receive code. This meant scheduler parameters were inadvertently
>> added to the migration stream, without proper consideration for how to
>> handle corner cases. The result was that if migrating from a host
>> running one scheduler to a host running a different scheduler, the
>> migration would fail with an error like the following:
>>
>> libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain 1:Getting
>> domain sched credit: Invalid argument
>> libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain 1:cannot
>> (re-)build domain: -3
>>
>> Luckily there's a fairly straightforward way to set parameters in a
>> "best-effort" fashion. libxl provides a single struct containing the
>> parameters of all schedulers, as well as a parameter specifying which
>> scheduler. Parameters not used by a given scheduler are ignored.
>> Additionally, the struct contains a parameter to specify the
>> scheduler. If you specify a specific scheduler,
>> libxl_domain_sched_params_set() will fail if there's a different
>> scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will use
>> the value of the current scheduler for that domain.
>>
>> In domcreate_stream_done(), before calling libxl__build_post(), set
>> the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
>> scheduler parameters from the previous instantiation on a best-effort
>> basis.
>>
>> Signed-off-by: George Dunlap
>> ---
>> CC: Ian Jackson
>> CC: Wei Liu
>> CC: Andrew Cooper
>> CC: Jan Beulich
>> CC: Dario Faggioli
>> CC: Juergen Gross
>> ---
>> tools/libxl/libxl_create.c | 9 +
>> 1 file changed, 9 insertions(+)
>>
>> diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
>> index dcfde7787e..caf79d4620 100644
>> --- a/tools/libxl/libxl_create.c
>> +++ b/tools/libxl/libxl_create.c
>> @@ -1237,6 +1237,15 @@ static void domcreate_stream_done(libxl__egc *egc,
>> ret = ERROR_INVAL;
>> goto out;
>> }
>> +
>> +/*
>> + * The scheduler on the sending domain may be different than the
>> + * scheduler running here. Setting the scheduler to UNKNOWN will
>> + * cause the code to take to take whatever parameters are
>> + * available in that scheduler, while discarding the rest.
>> + */
>> +info->sched_params.sched = LIBXL_SCHEDULER_UNKNOWN;
>
> But this function is called by normal domain creation as well. What if
> libxl user does set the parameter?
Is it? I thought the `stream` meant it was only called when doing
migrate / resume.
-George
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Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On Tue, Oct 02, 2018 at 04:49:26PM +0100, George Dunlap wrote:
> Commit 3b4adba ("tools/libxl: include scheduler parameters in the
> output of xl list -l") added scheduling parameters to the set of
> information collected by libxl_retrieve_domain_configuration(), in
> order to report that information in `xl list -l`.
>
> Unfortunately, libxl_retrieve_domain_configuration() is also called by
> the migration / save code, and the results passed to the restore /
> receive code. This meant scheduler parameters were inadvertently
> added to the migration stream, without proper consideration for how to
> handle corner cases. The result was that if migrating from a host
> running one scheduler to a host running a different scheduler, the
> migration would fail with an error like the following:
>
> libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain 1:Getting
> domain sched credit: Invalid argument
> libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain 1:cannot
> (re-)build domain: -3
>
> Luckily there's a fairly straightforward way to set parameters in a
> "best-effort" fashion. libxl provides a single struct containing the
> parameters of all schedulers, as well as a parameter specifying which
> scheduler. Parameters not used by a given scheduler are ignored.
> Additionally, the struct contains a parameter to specify the
> scheduler. If you specify a specific scheduler,
> libxl_domain_sched_params_set() will fail if there's a different
> scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will use
> the value of the current scheduler for that domain.
>
> In domcreate_stream_done(), before calling libxl__build_post(), set
> the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
> scheduler parameters from the previous instantiation on a best-effort
> basis.
>
> Signed-off-by: George Dunlap
> ---
> CC: Ian Jackson
> CC: Wei Liu
> CC: Andrew Cooper
> CC: Jan Beulich
> CC: Dario Faggioli
> CC: Juergen Gross
> ---
> tools/libxl/libxl_create.c | 9 +
> 1 file changed, 9 insertions(+)
>
> diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
> index dcfde7787e..caf79d4620 100644
> --- a/tools/libxl/libxl_create.c
> +++ b/tools/libxl/libxl_create.c
> @@ -1237,6 +1237,15 @@ static void domcreate_stream_done(libxl__egc *egc,
> ret = ERROR_INVAL;
> goto out;
> }
> +
> +/*
> + * The scheduler on the sending domain may be different than the
> + * scheduler running here. Setting the scheduler to UNKNOWN will
> + * cause the code to take to take whatever parameters are
> + * available in that scheduler, while discarding the rest.
> + */
> +info->sched_params.sched = LIBXL_SCHEDULER_UNKNOWN;
But this function is called by normal domain creation as well. What if
libxl user does set the parameter?
Wei.
> +
> ret = libxl__build_post(gc, domid, info, state, vments, localents);
> if (ret)
> goto out;
> --
> 2.19.0
>
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Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On Wed, 2018-10-03 at 12:53 +0200, Juergen Gross wrote:
> On 02/10/2018 17:49, George Dunlap wrote:
> > Commit 3b4adba ("tools/libxl: include scheduler parameters in the
> > output of xl list -l") added scheduling parameters to the set of
> > information collected by libxl_retrieve_domain_configuration(), in
> > order to report that information in `xl list -l`.
> >
> > Unfortunately, libxl_retrieve_domain_configuration() is also called
> > by
> > the migration / save code, and the results passed to the restore /
> > receive code. This meant scheduler parameters were inadvertently
> > added to the migration stream, without proper consideration for how
> > to
> > handle corner cases. The result was that if migrating from a host
> > running one scheduler to a host running a different scheduler, the
> > migration would fail with an error like the following:
> >
> > libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain
> > 1:Getting domain sched credit: Invalid argument
> > libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain
> > 1:cannot (re-)build domain: -3
> >
> > Luckily there's a fairly straightforward way to set parameters in a
> > "best-effort" fashion. libxl provides a single struct containing
> > the
> > parameters of all schedulers, as well as a parameter specifying
> > which
> > scheduler. Parameters not used by a given scheduler are ignored.
> > Additionally, the struct contains a parameter to specify the
> > scheduler. If you specify a specific scheduler,
> > libxl_domain_sched_params_set() will fail if there's a different
> > scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will
> > use
> > the value of the current scheduler for that domain.
> >
> > In domcreate_stream_done(), before calling libxl__build_post(), set
> > the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
> > scheduler parameters from the previous instantiation on a best-
> > effort
> > basis.
> >
> > Signed-off-by: George Dunlap
>
> Acked-by: Juergen Gross
>
Wei, Ian, ping?
We've reverted Credit2 as default scheduler, not because of a Credit2
own issue, but because of the bug fixed by this patch.
I think it would be both fair and appropriate to re-instate it (i.e.,
Credit2 as default), as soon as possible.
Regards,
Dario
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Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On Wed, 2018-10-03 at 12:53 +0200, Juergen Gross wrote:
> On 02/10/2018 17:49, George Dunlap wrote:
> > Commit 3b4adba ("tools/libxl: include scheduler parameters in the
> > output of xl list -l") added scheduling parameters to the set of
> > information collected by libxl_retrieve_domain_configuration(), in
> > order to report that information in `xl list -l`.
> >
> > Unfortunately, libxl_retrieve_domain_configuration() is also called
> > by
> > the migration / save code, and the results passed to the restore /
> > receive code. This meant scheduler parameters were inadvertently
> > added to the migration stream, without proper consideration for how
> > to
> > handle corner cases. The result was that if migrating from a host
> > running one scheduler to a host running a different scheduler, the
> > migration would fail with an error like the following:
> >
> > libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain
> > 1:Getting domain sched credit: Invalid argument
> > libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain
> > 1:cannot (re-)build domain: -3
> >
> > Luckily there's a fairly straightforward way to set parameters in a
> > "best-effort" fashion. libxl provides a single struct containing
> > the
> > parameters of all schedulers, as well as a parameter specifying
> > which
> > scheduler. Parameters not used by a given scheduler are ignored.
> > Additionally, the struct contains a parameter to specify the
> > scheduler. If you specify a specific scheduler,
> > libxl_domain_sched_params_set() will fail if there's a different
> > scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will
> > use
> > the value of the current scheduler for that domain.
> >
> > In domcreate_stream_done(), before calling libxl__build_post(), set
> > the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
> > scheduler parameters from the previous instantiation on a best-
> > effort
> > basis.
> >
> > Signed-off-by: George Dunlap
>
> Acked-by: Juergen Gross
>
Reviewed-by: Dario Faggioli
Dario
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-
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Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On 02/10/2018 17:49, George Dunlap wrote:
> Commit 3b4adba ("tools/libxl: include scheduler parameters in the
> output of xl list -l") added scheduling parameters to the set of
> information collected by libxl_retrieve_domain_configuration(), in
> order to report that information in `xl list -l`.
>
> Unfortunately, libxl_retrieve_domain_configuration() is also called by
> the migration / save code, and the results passed to the restore /
> receive code. This meant scheduler parameters were inadvertently
> added to the migration stream, without proper consideration for how to
> handle corner cases. The result was that if migrating from a host
> running one scheduler to a host running a different scheduler, the
> migration would fail with an error like the following:
>
> libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain 1:Getting
> domain sched credit: Invalid argument
> libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain 1:cannot
> (re-)build domain: -3
>
> Luckily there's a fairly straightforward way to set parameters in a
> "best-effort" fashion. libxl provides a single struct containing the
> parameters of all schedulers, as well as a parameter specifying which
> scheduler. Parameters not used by a given scheduler are ignored.
> Additionally, the struct contains a parameter to specify the
> scheduler. If you specify a specific scheduler,
> libxl_domain_sched_params_set() will fail if there's a different
> scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will use
> the value of the current scheduler for that domain.
>
> In domcreate_stream_done(), before calling libxl__build_post(), set
> the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
> scheduler parameters from the previous instantiation on a best-effort
> basis.
>
> Signed-off-by: George Dunlap
Acked-by: Juergen Gross
Juergen
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Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On 10/02/2018 04:49 PM, George Dunlap wrote:
> Commit 3b4adba ("tools/libxl: include scheduler parameters in the
> output of xl list -l") added scheduling parameters to the set of
> information collected by libxl_retrieve_domain_configuration(), in
> order to report that information in `xl list -l`.
>
> Unfortunately, libxl_retrieve_domain_configuration() is also called by
> the migration / save code, and the results passed to the restore /
> receive code. This meant scheduler parameters were inadvertently
> added to the migration stream, without proper consideration for how to
> handle corner cases. The result was that if migrating from a host
> running one scheduler to a host running a different scheduler, the
> migration would fail with an error like the following:
>
> libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain 1:Getting
> domain sched credit: Invalid argument
> libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain 1:cannot
> (re-)build domain: -3
>
> Luckily there's a fairly straightforward way to set parameters in a
> "best-effort" fashion. libxl provides a single struct containing the
> parameters of all schedulers, as well as a parameter specifying which
> scheduler. Parameters not used by a given scheduler are ignored.
> Additionally, the struct contains a parameter to specify the
> scheduler. If you specify a specific scheduler,
> libxl_domain_sched_params_set() will fail if there's a different
> scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will use
> the value of the current scheduler for that domain.
>
> In domcreate_stream_done(), before calling libxl__build_post(), set
> the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
> scheduler parameters from the previous instantiation on a best-effort
> basis.
>
> Signed-off-by: George Dunlap
I've tested this with save/restore now, and it works fine (including
changing the weight of the VM from default and having the updated weight
show up in the other scheduler on restore).
-George
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Re: [Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
On 10/02/2018 04:49 PM, George Dunlap wrote:
> Commit 3b4adba ("tools/libxl: include scheduler parameters in the
> output of xl list -l") added scheduling parameters to the set of
> information collected by libxl_retrieve_domain_configuration(), in
> order to report that information in `xl list -l`.
>
> Unfortunately, libxl_retrieve_domain_configuration() is also called by
> the migration / save code, and the results passed to the restore /
> receive code. This meant scheduler parameters were inadvertently
> added to the migration stream, without proper consideration for how to
> handle corner cases. The result was that if migrating from a host
> running one scheduler to a host running a different scheduler, the
> migration would fail with an error like the following:
>
> libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain 1:Getting
> domain sched credit: Invalid argument
> libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain 1:cannot
> (re-)build domain: -3
>
> Luckily there's a fairly straightforward way to set parameters in a
> "best-effort" fashion. libxl provides a single struct containing the
> parameters of all schedulers, as well as a parameter specifying which
> scheduler. Parameters not used by a given scheduler are ignored.
> Additionally, the struct contains a parameter to specify the
> scheduler. If you specify a specific scheduler,
> libxl_domain_sched_params_set() will fail if there's a different
> scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will use
> the value of the current scheduler for that domain.
>
> In domcreate_stream_done(), before calling libxl__build_post(), set
> the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
> scheduler parameters from the previous instantiation on a best-effort
> basis.
>
> Signed-off-by: George Dunlap
Sorry, forgot to mention this should be considered 'RFC' until I can
arrange to test it.
-George
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[Xen-devel] [PATCH] libxl: Restore scheduling parameters after migrate in best-effort fashion
Commit 3b4adba ("tools/libxl: include scheduler parameters in the
output of xl list -l") added scheduling parameters to the set of
information collected by libxl_retrieve_domain_configuration(), in
order to report that information in `xl list -l`.
Unfortunately, libxl_retrieve_domain_configuration() is also called by
the migration / save code, and the results passed to the restore /
receive code. This meant scheduler parameters were inadvertently
added to the migration stream, without proper consideration for how to
handle corner cases. The result was that if migrating from a host
running one scheduler to a host running a different scheduler, the
migration would fail with an error like the following:
libxl: error: libxl_sched.c:232:sched_credit_domain_set: Domain 1:Getting
domain sched credit: Invalid argument
libxl: error: libxl_create.c:1275:domcreate_rebuild_done: Domain 1:cannot
(re-)build domain: -3
Luckily there's a fairly straightforward way to set parameters in a
"best-effort" fashion. libxl provides a single struct containing the
parameters of all schedulers, as well as a parameter specifying which
scheduler. Parameters not used by a given scheduler are ignored.
Additionally, the struct contains a parameter to specify the
scheduler. If you specify a specific scheduler,
libxl_domain_sched_params_set() will fail if there's a different
scheduler. However, if you pass LIBXL_SCHEDULER_UNKNOWN, it will use
the value of the current scheduler for that domain.
In domcreate_stream_done(), before calling libxl__build_post(), set
the scheduler to LIBXL_SCHEDULER_UNKNOWN. This will propagate
scheduler parameters from the previous instantiation on a best-effort
basis.
Signed-off-by: George Dunlap
---
CC: Ian Jackson
CC: Wei Liu
CC: Andrew Cooper
CC: Jan Beulich
CC: Dario Faggioli
CC: Juergen Gross
---
tools/libxl/libxl_create.c | 9 +
1 file changed, 9 insertions(+)
diff --git a/tools/libxl/libxl_create.c b/tools/libxl/libxl_create.c
index dcfde7787e..caf79d4620 100644
--- a/tools/libxl/libxl_create.c
+++ b/tools/libxl/libxl_create.c
@@ -1237,6 +1237,15 @@ static void domcreate_stream_done(libxl__egc *egc,
ret = ERROR_INVAL;
goto out;
}
+
+/*
+ * The scheduler on the sending domain may be different than the
+ * scheduler running here. Setting the scheduler to UNKNOWN will
+ * cause the code to take to take whatever parameters are
+ * available in that scheduler, while discarding the rest.
+ */
+info->sched_params.sched = LIBXL_SCHEDULER_UNKNOWN;
+
ret = libxl__build_post(gc, domid, info, state, vments, localents);
if (ret)
goto out;
--
2.19.0
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