questions about hugetlb usage

questions about hugetlb usage

[Ma Shimiao]

Hello,

I'm new to cgroups.
I'm not sure whether this is the right place to ask questions about cgroups.
If not, I will be very sorry for disturbing.

Recently, I'm researching the usage of hugetlb.
I have got a problem, but don't know why and how to solve it.

# cat /proc/meminfo |grep -i huge
AnonHugePages:   1894400 kB
HugePages_Total:     192
HugePages_Free:      188
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
# cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.limit_in_bytes 
9223372036854771712
# cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.max_usage_in_bytes 
8388608
# cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.usage_in_bytes 
8388608
# echo 10240000000000 > /sys/fs/cgroup/hugetlb/hugetlb.2MB.limit_in_bytes 
-bash: echo: write error: Invalid argument

It seems I cant write values to hugetlb.2MB.limit_in_bytes
Could anyone give me some advice?
Thanks very much.

-- 
Ma Shimiao
Development Dept.I
Nanjing Fujitsu Nanda Software Tech. Co., Ltd.(FNST)

Re: questions about hugetlb usage

[Zefan Li]

On 2015/4/30 15:11, Ma Shimiao wrote:
> Hello,
> 
> I'm new to cgroups.
> I'm not sure whether this is the right place to ask questions about cgroups.
> If not, I will be very sorry for disturbing.
> 
> Recently, I'm researching the usage of hugetlb.
> I have got a problem, but don't know why and how to solve it.
> 
> # cat /proc/meminfo |grep -i huge
> AnonHugePages:   1894400 kB
> HugePages_Total:     192
> HugePages_Free:      188
> HugePages_Rsvd:        0
> HugePages_Surp:        0
> Hugepagesize:       2048 kB
> # cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.limit_in_bytes 
> 9223372036854771712
> # cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.max_usage_in_bytes 
> 8388608
> # cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.usage_in_bytes 
> 8388608
> # echo 10240000000000 > /sys/fs/cgroup/hugetlb/hugetlb.2MB.limit_in_bytes 
> -bash: echo: write error: Invalid argument
> 
> It seems I cant write values to hugetlb.2MB.limit_in_bytes
> Could anyone give me some advice?
> Thanks very much.
> 

Looks like you were trying to write to the file in root cgroup, which
is forbidden.

Re: questions about hugetlb usage

[Ma Shimiao]

On 04/30/2015 04:11 PM, Zefan Li wrote:
> On 2015/4/30 15:11, Ma Shimiao wrote:
>> Hello,
>>
>> I'm new to cgroups.
>> I'm not sure whether this is the right place to ask questions about cgroups.
>> If not, I will be very sorry for disturbing.
>>
>> Recently, I'm researching the usage of hugetlb.
>> I have got a problem, but don't know why and how to solve it.
>>
>> # cat /proc/meminfo |grep -i huge
>> AnonHugePages:   1894400 kB
>> HugePages_Total:     192
>> HugePages_Free:      188
>> HugePages_Rsvd:        0
>> HugePages_Surp:        0
>> Hugepagesize:       2048 kB
>> # cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.limit_in_bytes 
>> 9223372036854771712
>> # cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.max_usage_in_bytes 
>> 8388608
>> # cat /sys/fs/cgroup/hugetlb/hugetlb.2MB.usage_in_bytes 
>> 8388608
>> # echo 10240000000000 > /sys/fs/cgroup/hugetlb/hugetlb.2MB.limit_in_bytes 
>> -bash: echo: write error: Invalid argument
>>
>> It seems I cant write values to hugetlb.2MB.limit_in_bytes
>> Could anyone give me some advice?
>> Thanks very much.
>>
> 
> Looks like you were trying to write to the file in root cgroup, which
> is forbidden.
Ah...  
Tested. Really it is.
Thanks.
> 
> .
> 


-- 
Ma Shimiao
Development Dept.I
Nanjing Fujitsu Nanda Software Tech. Co., Ltd.(FNST)