search for: deflate_on_pressure

...That's *exactly* what "deflate on OOM" suggests. > > > > > > It seems there are some use cases where "deflate on OOM" is desired and > > others where "deflate on pressure" is desired. > > This suggests adding a new feature bit "DEFLATE_ON_PRESSURE" that > > registers the shrinker, and reverting DEFLATE_ON_OOM to use the OOM > > notifier callback. > > > > This lets users configure the balloon for their use case. > > You want the old behavior back, so why should we introduce a new one? Or > am I missing so...

...That's *exactly* what "deflate on OOM" suggests. > > > > > > It seems there are some use cases where "deflate on OOM" is desired and > > others where "deflate on pressure" is desired. > > This suggests adding a new feature bit "DEFLATE_ON_PRESSURE" that > > registers the shrinker, and reverting DEFLATE_ON_OOM to use the OOM > > notifier callback. > > > > This lets users configure the balloon for their use case. > > You want the old behavior back, so why should we introduce a new one? Or > am I missing so...

...ly* what "deflate on OOM" suggests. > > > > > > It seems there are some use cases where "deflate on OOM" is desired and > > others where "deflate on pressure" is desired. > > This suggests adding a new feature bit "DEFLATE_ON_PRESSURE" that > > registers the shrinker, and reverting DEFLATE_ON_OOM to use the OOM > > notifier callback. > > > > This lets users configure the balloon for their use case. > > You want the old behavior back, so why should we introduce a new one? Or...

...and impact application performance. > > That's *exactly* what "deflate on OOM" suggests. > It seems there are some use cases where "deflate on OOM" is desired and others where "deflate on pressure" is desired. This suggests adding a new feature bit "DEFLATE_ON_PRESSURE" that registers the shrinker, and reverting DEFLATE_ON_OOM to use the OOM notifier callback. This lets users configure the balloon for their use case. > > Assume you are using virtio-balloon for some weird way of memory > hotunplug (which is what some people do) and you want to min...

...and impact application performance. > > That's *exactly* what "deflate on OOM" suggests. > It seems there are some use cases where "deflate on OOM" is desired and others where "deflate on pressure" is desired. This suggests adding a new feature bit "DEFLATE_ON_PRESSURE" that registers the shrinker, and reverting DEFLATE_ON_OOM to use the OOM notifier callback. This lets users configure the balloon for their use case. > > Assume you are using virtio-balloon for some weird way of memory > hotunplug (which is what some people do) and you want to min...

...quot; suggests. > > > > > > > > > It seems there are some use cases where "deflate on OOM" is > desired and > > > others where "deflate on pressure" is desired. > > > This suggests adding a new feature bit "DEFLATE_ON_PRESSURE" that > > > registers the shrinker, and reverting DEFLATE_ON_OOM to use the OOM > > > notifier callback. > > > > > > This lets users configure the balloon for their use case. > > > > You want the old behavior back, so why shou...

...rformance. > > That's *exactly* what "deflate on OOM" suggests. > > > It seems there are some use cases where "deflate on OOM" is desired and > others where "deflate on pressure" is desired. > This suggests adding a new feature bit "DEFLATE_ON_PRESSURE" that > registers the shrinker, and reverting DEFLATE_ON_OOM to use the OOM > notifier callback. > > This lets users configure the balloon for their use case. You want the old behavior back, so why should we introduce a new one? Or am I missing something? (you did want us to reve...

There were apparently good reasons for moving away from OOM notifier callback: https://lkml.org/lkml/2018/7/12/314 https://lkml.org/lkml/2018/8/2/322 In particular the OOM notifier is worse than the shrinker because: 1. It is last-resort, which means the system has already gone through heroics to prevent OOM. Those heroic reclaim efforts are expensive and impact application performance.

There were apparently good reasons for moving away from OOM notifier callback: https://lkml.org/lkml/2018/7/12/314 https://lkml.org/lkml/2018/8/2/322 In particular the OOM notifier is worse than the shrinker because: 1. It is last-resort, which means the system has already gone through heroics to prevent OOM. Those heroic reclaim efforts are expensive and impact application performance.