On 2020-07-20 10:27, osalvador@xxxxxxx wrote:
On 2020-07-17 08:55, HORIGUCHI NAOYA wrote:
I ran Quan Cai's test program (https://github.com/cailca/linux-mm) on
a
small (4GB memory) VM, and weiredly found that (1) the target
hugepages
are not always dissolved and (2) dissovled hugetpages are still
counted
in "HugePages_Total:". See below:
$ ./random 1
- start: migrate_huge_offline
- use NUMA nodes 0,1.
- mmap and free 8388608 bytes hugepages on node 0
- mmap and free 8388608 bytes hugepages on node 1
madvise: Cannot allocate memory
$ cat /proc/meminfo
MemTotal: 4026772 kB
MemFree: 976300 kB
MemAvailable: 892840 kB
Buffers: 20936 kB
Cached: 99768 kB
SwapCached: 5904 kB
Active: 84332 kB
Inactive: 116328 kB
Active(anon): 27944 kB
Inactive(anon): 68524 kB
Active(file): 56388 kB
Inactive(file): 47804 kB
Unevictable: 7532 kB
Mlocked: 0 kB
SwapTotal: 2621436 kB
SwapFree: 2609844 kB
Dirty: 56 kB
Writeback: 0 kB
AnonPages: 81764 kB
Mapped: 54348 kB
Shmem: 8948 kB
KReclaimable: 22744 kB
Slab: 52056 kB
SReclaimable: 22744 kB
SUnreclaim: 29312 kB
KernelStack: 3888 kB
PageTables: 2804 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 3260612 kB
Committed_AS: 828196 kB
VmallocTotal: 34359738367 kB
VmallocUsed: 19260 kB
VmallocChunk: 0 kB
Percpu: 5120 kB
HardwareCorrupted: 5368 kB
AnonHugePages: 18432 kB
ShmemHugePages: 0 kB
ShmemPmdMapped: 0 kB
FileHugePages: 0 kB
FilePmdMapped: 0 kB
CmaTotal: 0 kB
CmaFree: 0 kB
HugePages_Total: 1342 // still counted as hugetlb pages.
HugePages_Free: 0 // all hugepage are still allocated
(or leaked?)
HugePages_Rsvd: 0
HugePages_Surp: 762 // some are counted in surplus.
Hugepagesize: 2048 kB
Hugetlb: 2748416 kB
DirectMap4k: 112480 kB
DirectMap2M: 4081664 kB
$ page-types -b hwpoison
flags page-count MB symbolic-flags
long-symbolic-flags
0x0000000000080008 421 1
___U_______________X_______________________ uptodate,hwpoison
0x00000000000a8018 1 0
___UD__________H_G_X_______________________
uptodate,dirty,compound_head,huge,hwpoison
0x00000000000a801c 920 3
__RUD__________H_G_X_______________________
referenced,uptodate,dirty,compound_head,huge,hwpoison
total 1342 5
This means that some hugepages are dissolved, but the others not,
maybe which is not desirable.
I'll dig this more later but just let me share at first.
A few minor comment below ...
Uhm, weird.
I will be taking a look today.
After some digging up I __think__ I found the problem.
I will try to fix it up and I will be running tests.
I might reach out to you once I am done because I remember you had a
test-suite that worked quite well, so you can give it a spin there.
Thanks
