| Message ID | 20220201151136.52157-1-jinpu.wang@ionos.com |
|---|---|
| State | New |
| Headers | show |
| Series | [1/2] migration/rdma: Increase the backlog from 5 to 128 | expand |
> So it can handle more incoming requests. > > Signed-off-by: Jack Wang <jinpu.wang@ionos.com> > --- > migration/rdma.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/migration/rdma.c b/migration/rdma.c > index c7c7a384875b..2e223170d06d 100644 > --- a/migration/rdma.c > +++ b/migration/rdma.c > @@ -4238,7 +4238,7 @@ void rdma_start_incoming_migration(const char *host_port, Error **errp) > > trace_rdma_start_incoming_migration_after_dest_init(); > > - ret = rdma_listen(rdma->listen_id, 5); > + ret = rdma_listen(rdma->listen_id, 128); 128 backlog seems too much to me. Any reason for choosing this number. Any rationale to choose this number? Thanks, Pankaj > > if (ret) { > ERROR(errp, "listening on socket!"); > -- > 2.25.1 >
On Tue, Feb 1, 2022 at 7:19 PM Pankaj Gupta <pankaj.gupta@ionos.com> wrote: > > > So it can handle more incoming requests. > > > > Signed-off-by: Jack Wang <jinpu.wang@ionos.com> > > --- > > migration/rdma.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/migration/rdma.c b/migration/rdma.c > > index c7c7a384875b..2e223170d06d 100644 > > --- a/migration/rdma.c > > +++ b/migration/rdma.c > > @@ -4238,7 +4238,7 @@ void rdma_start_incoming_migration(const char *host_port, Error **errp) > > > > trace_rdma_start_incoming_migration_after_dest_init(); > > > > - ret = rdma_listen(rdma->listen_id, 5); > > + ret = rdma_listen(rdma->listen_id, 128); > > 128 backlog seems too much to me. Any reason for choosing this number. > Any rationale to choose this number? > 128 is the default value of SOMAXCONN, I can use that if it is preferred. > Thanks, > Pankaj Thanks! > > > > > if (ret) { > > ERROR(errp, "listening on socket!"); > > -- > > 2.25.1 > >
> > > So it can handle more incoming requests. > > > > > > Signed-off-by: Jack Wang <jinpu.wang@ionos.com> > > > --- > > > migration/rdma.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/migration/rdma.c b/migration/rdma.c > > > index c7c7a384875b..2e223170d06d 100644 > > > --- a/migration/rdma.c > > > +++ b/migration/rdma.c > > > @@ -4238,7 +4238,7 @@ void rdma_start_incoming_migration(const char *host_port, Error **errp) > > > > > > trace_rdma_start_incoming_migration_after_dest_init(); > > > > > > - ret = rdma_listen(rdma->listen_id, 5); > > > + ret = rdma_listen(rdma->listen_id, 128); > > > > 128 backlog seems too much to me. Any reason for choosing this number. > > Any rationale to choose this number? > > > 128 is the default value of SOMAXCONN, I can use that if it is preferred. AFAICS backlog is only applicable with RDMA iWARP CM mode. Maybe we can increase it to 128. Maybe you can also share any testing data for multiple concurrent live migrations using RDMA, please. Thanks, Pankaj Thanks, Pankaj
> > > > migration/rdma.c | 2 +- > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > diff --git a/migration/rdma.c b/migration/rdma.c > > > > index c7c7a384875b..2e223170d06d 100644 > > > > --- a/migration/rdma.c > > > > +++ b/migration/rdma.c > > > > @@ -4238,7 +4238,7 @@ void rdma_start_incoming_migration(const char *host_port, Error **errp) > > > > > > > > trace_rdma_start_incoming_migration_after_dest_init(); > > > > > > > > - ret = rdma_listen(rdma->listen_id, 5); > > > > + ret = rdma_listen(rdma->listen_id, 128); > > > > > > 128 backlog seems too much to me. Any reason for choosing this number. > > > Any rationale to choose this number? > > > > > 128 is the default value of SOMAXCONN, I can use that if it is preferred. > > AFAICS backlog is only applicable with RDMA iWARP CM mode. Maybe we > can increase it to 128.these many Or maybe we first increase it to 20 or 32? or so to avoid memory overhead if we are not using these many connections at the same time. > Maybe you can also share any testing data for multiple concurrent live > migrations using RDMA, please. > > Thanks, > Pankaj > > Thanks, > Pankaj
* Pankaj Gupta (pankaj.gupta@ionos.com) wrote: > > > > > migration/rdma.c | 2 +- > > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > > > diff --git a/migration/rdma.c b/migration/rdma.c > > > > > index c7c7a384875b..2e223170d06d 100644 > > > > > --- a/migration/rdma.c > > > > > +++ b/migration/rdma.c > > > > > @@ -4238,7 +4238,7 @@ void rdma_start_incoming_migration(const char *host_port, Error **errp) > > > > > > > > > > trace_rdma_start_incoming_migration_after_dest_init(); > > > > > > > > > > - ret = rdma_listen(rdma->listen_id, 5); > > > > > + ret = rdma_listen(rdma->listen_id, 128); > > > > > > > > 128 backlog seems too much to me. Any reason for choosing this number. > > > > Any rationale to choose this number? > > > > > > > 128 is the default value of SOMAXCONN, I can use that if it is preferred. > > > > AFAICS backlog is only applicable with RDMA iWARP CM mode. Maybe we > > can increase it to 128.these many > > Or maybe we first increase it to 20 or 32? or so to avoid memory > overhead if we are not > using these many connections at the same time. Can you explain why you're requiring more than 1? Is this with multifd patches? Dave > > Maybe you can also share any testing data for multiple concurrent live > > migrations using RDMA, please. > > > > Thanks, > > Pankaj > > > > Thanks, > > Pankaj >
On Wed, Feb 2, 2022 at 10:20 AM Dr. David Alan Gilbert <dgilbert@redhat.com> wrote: > > * Pankaj Gupta (pankaj.gupta@ionos.com) wrote: > > > > > > migration/rdma.c | 2 +- > > > > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > > > > > > > diff --git a/migration/rdma.c b/migration/rdma.c > > > > > > index c7c7a384875b..2e223170d06d 100644 > > > > > > --- a/migration/rdma.c > > > > > > +++ b/migration/rdma.c > > > > > > @@ -4238,7 +4238,7 @@ void rdma_start_incoming_migration(const char *host_port, Error **errp) > > > > > > > > > > > > trace_rdma_start_incoming_migration_after_dest_init(); > > > > > > > > > > > > - ret = rdma_listen(rdma->listen_id, 5); > > > > > > + ret = rdma_listen(rdma->listen_id, 128); > > > > > > > > > > 128 backlog seems too much to me. Any reason for choosing this number. > > > > > Any rationale to choose this number? > > > > > > > > > 128 is the default value of SOMAXCONN, I can use that if it is preferred. > > > > > > AFAICS backlog is only applicable with RDMA iWARP CM mode. Maybe we > > > can increase it to 128.these many > > > > Or maybe we first increase it to 20 or 32? or so to avoid memory > > overhead if we are not > > using these many connections at the same time. > > Can you explain why you're requiring more than 1? Is this with multifd > patches? no, I'm not using multifs patches, just code reading, I feel 5 is too small for the backlog setting. As Pankaj rightly mentioned, in RDMA, only iWARP CM will take some effect, it does nothing for InfiniBand and RoCE. Please ignore this patch, we can revisit this when we introduce multifid with RDMA. Thanks! Jinpu Wang > > Dave > > > > Maybe you can also share any testing data for multiple concurrent live > > > migrations using RDMA, please. > > > > > > Thanks, > > > Pankaj > > > > > > Thanks, > > > Pankaj > > > -- > Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK >
diff --git a/migration/rdma.c b/migration/rdma.c index c7c7a384875b..2e223170d06d 100644 --- a/migration/rdma.c +++ b/migration/rdma.c @@ -4238,7 +4238,7 @@ void rdma_start_incoming_migration(const char *host_port, Error **errp) trace_rdma_start_incoming_migration_after_dest_init(); - ret = rdma_listen(rdma->listen_id, 5); + ret = rdma_listen(rdma->listen_id, 128); if (ret) { ERROR(errp, "listening on socket!");
So it can handle more incoming requests. Signed-off-by: Jack Wang <jinpu.wang@ionos.com> --- migration/rdma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)