| Message ID | 20210421070059.69361-1-songmuchun@bytedance.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | Use obj_cgroup APIs to charge the LRU pages | expand |
Ping... Hi Johannes and Roman, Any suggestions on this patch set? Thanks. On Wed, Apr 21, 2021 at 3:01 PM Muchun Song <songmuchun@bytedance.com> wrote: > > This is v3 based on the top of the series[1] (memcontrol code cleanup and > simplification). Roman is working on the generalization of obj_cgroup API. > But before that, hope someone can review this patches for correctness. > > Since the following patchsets applied. All the kernel memory are charged > with the new APIs of obj_cgroup. > > [v17,00/19] The new cgroup slab memory controller[2] > [v5,0/7] Use obj_cgroup APIs to charge kmem pages[3] > > But user memory allocations (LRU pages) pinning memcgs for a long time - > it exists at a larger scale and is causing recurring problems in the real > world: page cache doesn't get reclaimed for a long time, or is used by the > second, third, fourth, ... instance of the same job that was restarted into > a new cgroup every time. Unreclaimable dying cgroups pile up, waste memory, > and make page reclaim very inefficient. > > We can convert LRU pages and most other raw memcg pins to the objcg direction > to fix this problem, and then the LRU pages will not pin the memcgs. > > This patchset aims to make the LRU pages to drop the reference to memory > cgroup by using the APIs of obj_cgroup. Finally, we can see that the number > of the dying cgroups will not increase if we run the following test script. > > ```bash > #!/bin/bash > > cat /proc/cgroups | grep memory > > cd /sys/fs/cgroup/memory > > for i in range{1..500} > do > mkdir test > echo $$ > test/cgroup.procs > sleep 60 & > echo $$ > cgroup.procs > echo `cat test/cgroup.procs` > cgroup.procs > rmdir test > done > > cat /proc/cgroups | grep memory > ``` > > Thanks. > > [1] https://lore.kernel.org/linux-mm/20210417043538.9793-1-songmuchun@bytedance.com/ > [2] https://lore.kernel.org/linux-mm/20200623015846.1141975-1-guro@fb.com/ > [3] https://lore.kernel.org/linux-mm/20210319163821.20704-1-songmuchun@bytedance.com/ > > Changlogs in RFC v3: > 1. Drop the code cleanup and simplification patches. Gather those patches > into a separate series[1]. > 2. Rework patch #1 suggested by Johannes. > > Changlogs in RFC v2: > 1. Collect Acked-by tags by Johannes. Thanks. > 2. Rework lruvec_holds_page_lru_lock() suggested by Johannes. Thanks. > 3. Fix move_pages_to_lru(). > > Muchun Song (12): > mm: memcontrol: move the objcg infrastructure out of CONFIG_MEMCG_KMEM > mm: memcontrol: introduce compact_lock_page_lruvec_irqsave > mm: memcontrol: make lruvec lock safe when the LRU pages reparented > mm: vmscan: rework move_pages_to_lru() > mm: thp: introduce lock/unlock_split_queue{_irqsave}() > mm: thp: make deferred split queue lock safe when the LRU pages > reparented > mm: memcontrol: make all the callers of page_memcg() safe > mm: memcontrol: introduce memcg_reparent_ops > mm: memcontrol: use obj_cgroup APIs to charge the LRU pages > mm: memcontrol: rename {un}lock_page_memcg() to {un}lock_page_objcg() > mm: lru: add VM_BUG_ON_PAGE to lru maintenance function > mm: lru: use lruvec lock to serialize memcg changes > > Documentation/admin-guide/cgroup-v1/memory.rst | 2 +- > fs/buffer.c | 13 +- > fs/fs-writeback.c | 23 +- > fs/iomap/buffered-io.c | 4 +- > include/linux/memcontrol.h | 182 ++++---- > include/linux/mm_inline.h | 6 + > mm/compaction.c | 36 +- > mm/filemap.c | 2 +- > mm/huge_memory.c | 171 ++++++-- > mm/memcontrol.c | 562 ++++++++++++++++++------- > mm/migrate.c | 4 + > mm/page-writeback.c | 24 +- > mm/page_io.c | 5 +- > mm/rmap.c | 14 +- > mm/swap.c | 46 +- > mm/vmscan.c | 56 ++- > 16 files changed, 795 insertions(+), 355 deletions(-) > > -- > 2.11.0 >
Hi Muchun! It looks like the writeback problem will be solved in a different way, which will not require generalization of the obj_cgroup api to the cgroup level. It’s not fully confirmed yet though. We still might wanna do this generalization lingn-term, but as now I have no objections for continuing the work on your patchset. I’m on pto this week, but will take a deeper look at your patches early next week. Sorry for the delay. Thanks! Sent from my iPhone > On May 18, 2021, at 06:50, Muchun Song <songmuchun@bytedance.com> wrote: > > Ping... > > Hi Johannes and Roman, > > Any suggestions on this patch set? > > Thanks. > >> On Wed, Apr 21, 2021 at 3:01 PM Muchun Song <songmuchun@bytedance.com> wrote: >> >> This is v3 based on the top of the series[1] (memcontrol code cleanup and >> simplification). Roman is working on the generalization of obj_cgroup API. >> But before that, hope someone can review this patches for correctness. >> >> Since the following patchsets applied. All the kernel memory are charged >> with the new APIs of obj_cgroup. >> >> [v17,00/19] The new cgroup slab memory controller[2] >> [v5,0/7] Use obj_cgroup APIs to charge kmem pages[3] >> >> But user memory allocations (LRU pages) pinning memcgs for a long time - >> it exists at a larger scale and is causing recurring problems in the real >> world: page cache doesn't get reclaimed for a long time, or is used by the >> second, third, fourth, ... instance of the same job that was restarted into >> a new cgroup every time. Unreclaimable dying cgroups pile up, waste memory, >> and make page reclaim very inefficient. >> >> We can convert LRU pages and most other raw memcg pins to the objcg direction >> to fix this problem, and then the LRU pages will not pin the memcgs. >> >> This patchset aims to make the LRU pages to drop the reference to memory >> cgroup by using the APIs of obj_cgroup. Finally, we can see that the number >> of the dying cgroups will not increase if we run the following test script. >> >> ```bash >> #!/bin/bash >> >> cat /proc/cgroups | grep memory >> >> cd /sys/fs/cgroup/memory >> >> for i in range{1..500} >> do >> mkdir test >> echo $$ > test/cgroup.procs >> sleep 60 & >> echo $$ > cgroup.procs >> echo `cat test/cgroup.procs` > cgroup.procs >> rmdir test >> done >> >> cat /proc/cgroups | grep memory >> ``` >> >> Thanks. >> >> [1] https://lore.kernel.org/linux-mm/20210417043538.9793-1-songmuchun@bytedance.com/ >> [2] https://lore.kernel.org/linux-mm/20200623015846.1141975-1-guro@fb.com/ >> [3] https://lore.kernel.org/linux-mm/20210319163821.20704-1-songmuchun@bytedance.com/ >> >> Changlogs in RFC v3: >> 1. Drop the code cleanup and simplification patches. Gather those patches >> into a separate series[1]. >> 2. Rework patch #1 suggested by Johannes. >> >> Changlogs in RFC v2: >> 1. Collect Acked-by tags by Johannes. Thanks. >> 2. Rework lruvec_holds_page_lru_lock() suggested by Johannes. Thanks. >> 3. Fix move_pages_to_lru(). >> >> Muchun Song (12): >> mm: memcontrol: move the objcg infrastructure out of CONFIG_MEMCG_KMEM >> mm: memcontrol: introduce compact_lock_page_lruvec_irqsave >> mm: memcontrol: make lruvec lock safe when the LRU pages reparented >> mm: vmscan: rework move_pages_to_lru() >> mm: thp: introduce lock/unlock_split_queue{_irqsave}() >> mm: thp: make deferred split queue lock safe when the LRU pages >> reparented >> mm: memcontrol: make all the callers of page_memcg() safe >> mm: memcontrol: introduce memcg_reparent_ops >> mm: memcontrol: use obj_cgroup APIs to charge the LRU pages >> mm: memcontrol: rename {un}lock_page_memcg() to {un}lock_page_objcg() >> mm: lru: add VM_BUG_ON_PAGE to lru maintenance function >> mm: lru: use lruvec lock to serialize memcg changes >> >> Documentation/admin-guide/cgroup-v1/memory.rst | 2 +- >> fs/buffer.c | 13 +- >> fs/fs-writeback.c | 23 +- >> fs/iomap/buffered-io.c | 4 +- >> include/linux/memcontrol.h | 182 ++++---- >> include/linux/mm_inline.h | 6 + >> mm/compaction.c | 36 +- >> mm/filemap.c | 2 +- >> mm/huge_memory.c | 171 ++++++-- >> mm/memcontrol.c | 562 ++++++++++++++++++------- >> mm/migrate.c | 4 + >> mm/page-writeback.c | 24 +- >> mm/page_io.c | 5 +- >> mm/rmap.c | 14 +- >> mm/swap.c | 46 +- >> mm/vmscan.c | 56 ++- >> 16 files changed, 795 insertions(+), 355 deletions(-) >> >> -- >> 2.11.0 >>
On Tue, May 18, 2021 at 10:17 PM Roman Gushchin <guro@fb.com> wrote: > > Hi Muchun! > > It looks like the writeback problem will be solved in a different way, which will not require generalization of the obj_cgroup api to the cgroup level. It’s not fully confirmed yet though. We still might wanna do this generalization lingn-term, but as now I have no objections for continuing the work on your patchset. I’m on pto this week, but will take a deeper look at your patches early next week. Sorry for the delay. Waiting on your review. Thanks Roman. > > Thanks! > > Sent from my iPhone > > > On May 18, 2021, at 06:50, Muchun Song <songmuchun@bytedance.com> wrote: > > > > Ping... > > > > Hi Johannes and Roman, > > > > Any suggestions on this patch set? > > > > Thanks. > > > >> On Wed, Apr 21, 2021 at 3:01 PM Muchun Song <songmuchun@bytedance.com> wrote: > >> > >> This is v3 based on the top of the series[1] (memcontrol code cleanup and > >> simplification). Roman is working on the generalization of obj_cgroup API. > >> But before that, hope someone can review this patches for correctness. > >> > >> Since the following patchsets applied. All the kernel memory are charged > >> with the new APIs of obj_cgroup. > >> > >> [v17,00/19] The new cgroup slab memory controller[2] > >> [v5,0/7] Use obj_cgroup APIs to charge kmem pages[3] > >> > >> But user memory allocations (LRU pages) pinning memcgs for a long time - > >> it exists at a larger scale and is causing recurring problems in the real > >> world: page cache doesn't get reclaimed for a long time, or is used by the > >> second, third, fourth, ... instance of the same job that was restarted into > >> a new cgroup every time. Unreclaimable dying cgroups pile up, waste memory, > >> and make page reclaim very inefficient. > >> > >> We can convert LRU pages and most other raw memcg pins to the objcg direction > >> to fix this problem, and then the LRU pages will not pin the memcgs. > >> > >> This patchset aims to make the LRU pages to drop the reference to memory > >> cgroup by using the APIs of obj_cgroup. Finally, we can see that the number > >> of the dying cgroups will not increase if we run the following test script. > >> > >> ```bash > >> #!/bin/bash > >> > >> cat /proc/cgroups | grep memory > >> > >> cd /sys/fs/cgroup/memory > >> > >> for i in range{1..500} > >> do > >> mkdir test > >> echo $$ > test/cgroup.procs > >> sleep 60 & > >> echo $$ > cgroup.procs > >> echo `cat test/cgroup.procs` > cgroup.procs > >> rmdir test > >> done > >> > >> cat /proc/cgroups | grep memory > >> ``` > >> > >> Thanks. > >> > >> [1] https://lore.kernel.org/linux-mm/20210417043538.9793-1-songmuchun@bytedance.com/ > >> [2] https://lore.kernel.org/linux-mm/20200623015846.1141975-1-guro@fb.com/ > >> [3] https://lore.kernel.org/linux-mm/20210319163821.20704-1-songmuchun@bytedance.com/ > >> > >> Changlogs in RFC v3: > >> 1. Drop the code cleanup and simplification patches. Gather those patches > >> into a separate series[1]. > >> 2. Rework patch #1 suggested by Johannes. > >> > >> Changlogs in RFC v2: > >> 1. Collect Acked-by tags by Johannes. Thanks. > >> 2. Rework lruvec_holds_page_lru_lock() suggested by Johannes. Thanks. > >> 3. Fix move_pages_to_lru(). > >> > >> Muchun Song (12): > >> mm: memcontrol: move the objcg infrastructure out of CONFIG_MEMCG_KMEM > >> mm: memcontrol: introduce compact_lock_page_lruvec_irqsave > >> mm: memcontrol: make lruvec lock safe when the LRU pages reparented > >> mm: vmscan: rework move_pages_to_lru() > >> mm: thp: introduce lock/unlock_split_queue{_irqsave}() > >> mm: thp: make deferred split queue lock safe when the LRU pages > >> reparented > >> mm: memcontrol: make all the callers of page_memcg() safe > >> mm: memcontrol: introduce memcg_reparent_ops > >> mm: memcontrol: use obj_cgroup APIs to charge the LRU pages > >> mm: memcontrol: rename {un}lock_page_memcg() to {un}lock_page_objcg() > >> mm: lru: add VM_BUG_ON_PAGE to lru maintenance function > >> mm: lru: use lruvec lock to serialize memcg changes > >> > >> Documentation/admin-guide/cgroup-v1/memory.rst | 2 +- > >> fs/buffer.c | 13 +- > >> fs/fs-writeback.c | 23 +- > >> fs/iomap/buffered-io.c | 4 +- > >> include/linux/memcontrol.h | 182 ++++---- > >> include/linux/mm_inline.h | 6 + > >> mm/compaction.c | 36 +- > >> mm/filemap.c | 2 +- > >> mm/huge_memory.c | 171 ++++++-- > >> mm/memcontrol.c | 562 ++++++++++++++++++------- > >> mm/migrate.c | 4 + > >> mm/page-writeback.c | 24 +- > >> mm/page_io.c | 5 +- > >> mm/rmap.c | 14 +- > >> mm/swap.c | 46 +- > >> mm/vmscan.c | 56 ++- > >> 16 files changed, 795 insertions(+), 355 deletions(-) > >> > >> -- > >> 2.11.0 > >>
On Thu, May 20, 2021 at 11:20:47AM +0800, Muchun Song wrote: > On Tue, May 18, 2021 at 10:17 PM Roman Gushchin <guro@fb.com> wrote: > > > > Hi Muchun! > > > > It looks like the writeback problem will be solved in a different way, which will not require generalization of the obj_cgroup api to the cgroup level. It’s not fully confirmed yet though. We still might wanna do this generalization lingn-term, but as now I have no objections for continuing the work on your patchset. I’m on pto this week, but will take a deeper look at your patches early next week. Sorry for the delay. > > Waiting on your review. Thanks Roman. It looks like the mm tree went ahead and I can't clearly apply the whole patchset. Would you mind to rebase it and resend? Thank you!
On Wed, May 26, 2021 at 1:35 AM Roman Gushchin <guro@fb.com> wrote: > > On Thu, May 20, 2021 at 11:20:47AM +0800, Muchun Song wrote: > > On Tue, May 18, 2021 at 10:17 PM Roman Gushchin <guro@fb.com> wrote: > > > > > > Hi Muchun! > > > > > > It looks like the writeback problem will be solved in a different way, which will not require generalization of the obj_cgroup api to the cgroup level. It’s not fully confirmed yet though. We still might wanna do this generalization lingn-term, but as now I have no objections for continuing the work on your patchset. I’m on pto this week, but will take a deeper look at your patches early next week. Sorry for the delay. > > > > Waiting on your review. Thanks Roman. > > It looks like the mm tree went ahead and I can't clearly apply the whole patchset. > Would you mind to rebase it and resend? Got it. Will do that. Thanks. > > Thank you!
This is v3 based on the top of the series[1] (memcontrol code cleanup and simplification). Roman is working on the generalization of obj_cgroup API. But before that, hope someone can review this patches for correctness. Since the following patchsets applied. All the kernel memory are charged with the new APIs of obj_cgroup. [v17,00/19] The new cgroup slab memory controller[2] [v5,0/7] Use obj_cgroup APIs to charge kmem pages[3] But user memory allocations (LRU pages) pinning memcgs for a long time - it exists at a larger scale and is causing recurring problems in the real world: page cache doesn't get reclaimed for a long time, or is used by the second, third, fourth, ... instance of the same job that was restarted into a new cgroup every time. Unreclaimable dying cgroups pile up, waste memory, and make page reclaim very inefficient. We can convert LRU pages and most other raw memcg pins to the objcg direction to fix this problem, and then the LRU pages will not pin the memcgs. This patchset aims to make the LRU pages to drop the reference to memory cgroup by using the APIs of obj_cgroup. Finally, we can see that the number of the dying cgroups will not increase if we run the following test script. ```bash #!/bin/bash cat /proc/cgroups | grep memory cd /sys/fs/cgroup/memory for i in range{1..500} do mkdir test echo $$ > test/cgroup.procs sleep 60 & echo $$ > cgroup.procs echo `cat test/cgroup.procs` > cgroup.procs rmdir test done cat /proc/cgroups | grep memory ``` Thanks. [1] https://lore.kernel.org/linux-mm/20210417043538.9793-1-songmuchun@bytedance.com/ [2] https://lore.kernel.org/linux-mm/20200623015846.1141975-1-guro@fb.com/ [3] https://lore.kernel.org/linux-mm/20210319163821.20704-1-songmuchun@bytedance.com/ Changlogs in RFC v3: 1. Drop the code cleanup and simplification patches. Gather those patches into a separate series[1]. 2. Rework patch #1 suggested by Johannes. Changlogs in RFC v2: 1. Collect Acked-by tags by Johannes. Thanks. 2. Rework lruvec_holds_page_lru_lock() suggested by Johannes. Thanks. 3. Fix move_pages_to_lru(). Muchun Song (12): mm: memcontrol: move the objcg infrastructure out of CONFIG_MEMCG_KMEM mm: memcontrol: introduce compact_lock_page_lruvec_irqsave mm: memcontrol: make lruvec lock safe when the LRU pages reparented mm: vmscan: rework move_pages_to_lru() mm: thp: introduce lock/unlock_split_queue{_irqsave}() mm: thp: make deferred split queue lock safe when the LRU pages reparented mm: memcontrol: make all the callers of page_memcg() safe mm: memcontrol: introduce memcg_reparent_ops mm: memcontrol: use obj_cgroup APIs to charge the LRU pages mm: memcontrol: rename {un}lock_page_memcg() to {un}lock_page_objcg() mm: lru: add VM_BUG_ON_PAGE to lru maintenance function mm: lru: use lruvec lock to serialize memcg changes Documentation/admin-guide/cgroup-v1/memory.rst | 2 +- fs/buffer.c | 13 +- fs/fs-writeback.c | 23 +- fs/iomap/buffered-io.c | 4 +- include/linux/memcontrol.h | 182 ++++---- include/linux/mm_inline.h | 6 + mm/compaction.c | 36 +- mm/filemap.c | 2 +- mm/huge_memory.c | 171 ++++++-- mm/memcontrol.c | 562 ++++++++++++++++++------- mm/migrate.c | 4 + mm/page-writeback.c | 24 +- mm/page_io.c | 5 +- mm/rmap.c | 14 +- mm/swap.c | 46 +- mm/vmscan.c | 56 ++- 16 files changed, 795 insertions(+), 355 deletions(-)