Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[Donny Davis]

I was just curious, and I concur that there is no logic in not just using
the defaults.

On Thu, Jan 4, 2018 at 1:46 PM, Yaniv Kaul  wrote:

>
>
> On Jan 4, 2018 7:01 PM, "Donny Davis"  wrote:
>
> Yaniv,
>
> If there was a central logging server, would the hypervisors send them
> there and stop writing to disk (given its setup properly), or does it write
> them anyway?
>
>
> We ship logs to the central logging, not instead of logging them locally.
> I reckon you could mount /var/log somewhere remotely, but I do not think
> it makes sense.
> Our logging is not intensive and has log rotation configured, so I'm not
> sure what the issue is. A r/o partition or a cheap SD card with limited
> write wear?
> Y.
>
>
>
> https://www.ovirt.org/documentation/admin-guide/chap-Log_Files/
>
> On Thu, Jan 4, 2018 at 11:43 AM, Yaniv Kaul  wrote:
>
>>
>>
>> On Thu, Jan 4, 2018 at 5:04 PM, Donny Davis  wrote:
>>
>>> That makes more sense. Have you measured the write load on the disks
>>> from just the hypervisor processes. I have included a screen shot from
>>> mine, and the load is very low in the Kilobytes/sec
>>>
>>
>> And those are probably the logs, which will be written anyway...
>> Y.
>>
>>
>>>
>>> I am not sure of the implications of changing these parameters, and I do
>>> not see an perceivable benefits from doing so.
>>>
>>> [image: Inline image 1]
>>>
>>> On Thu, Jan 4, 2018 at 9:51 AM, andreil1  wrote:
>>>


 On 4 Jan 2018, at 14:52, Donny Davis  wrote:

 What is the purpose in putting these directives in for the hypervisor?


 I have small node where system and data domains located on the same
 RAID.
 Data domains are on separate partitions.
 These options allow minimise disk access activity.


 On Thu, Jan 4, 2018 at 6:46 AM, andreil1  wrote:

> Hi !
>
> Is it safe to turn on these options (noatime, nodiratime) in oVirt
> node fstab for these mount points?
> /home
> /
> /tmp
> /var
> /var/log
> /var/log/audit
>
> Node 4.2 installed on CentOS, not with node DVD.
>
> Thanks.
>
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>



 ___
 Users mailing list
 Users@ovirt.org
 http://lists.ovirt.org/mailman/listinfo/users


>>>
>>> ___
>>> Users mailing list
>>> Users@ovirt.org
>>> http://lists.ovirt.org/mailman/listinfo/users
>>>
>>>
>>
>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[Yaniv Kaul]

On Jan 4, 2018 7:01 PM, "Donny Davis"  wrote:

Yaniv,

If there was a central logging server, would the hypervisors send them
there and stop writing to disk (given its setup properly), or does it write
them anyway?


We ship logs to the central logging, not instead of logging them locally.
I reckon you could mount /var/log somewhere remotely, but I do not think it
makes sense.
Our logging is not intensive and has log rotation configured, so I'm not
sure what the issue is. A r/o partition or a cheap SD card with limited
write wear?
Y.



https://www.ovirt.org/documentation/admin-guide/chap-Log_Files/

On Thu, Jan 4, 2018 at 11:43 AM, Yaniv Kaul  wrote:

>
>
> On Thu, Jan 4, 2018 at 5:04 PM, Donny Davis  wrote:
>
>> That makes more sense. Have you measured the write load on the disks from
>> just the hypervisor processes. I have included a screen shot from mine, and
>> the load is very low in the Kilobytes/sec
>>
>
> And those are probably the logs, which will be written anyway...
> Y.
>
>
>>
>> I am not sure of the implications of changing these parameters, and I do
>> not see an perceivable benefits from doing so.
>>
>> [image: Inline image 1]
>>
>> On Thu, Jan 4, 2018 at 9:51 AM, andreil1  wrote:
>>
>>>
>>>
>>> On 4 Jan 2018, at 14:52, Donny Davis  wrote:
>>>
>>> What is the purpose in putting these directives in for the hypervisor?
>>>
>>>
>>> I have small node where system and data domains located on the same RAID.
>>> Data domains are on separate partitions.
>>> These options allow minimise disk access activity.
>>>
>>>
>>> On Thu, Jan 4, 2018 at 6:46 AM, andreil1  wrote:
>>>
 Hi !

 Is it safe to turn on these options (noatime, nodiratime) in oVirt node
 fstab for these mount points?
 /home
 /
 /tmp
 /var
 /var/log
 /var/log/audit

 Node 4.2 installed on CentOS, not with node DVD.

 Thanks.

 ___
 Users mailing list
 Users@ovirt.org
 http://lists.ovirt.org/mailman/listinfo/users

>>>
>>>
>>>
>>> ___
>>> Users mailing list
>>> Users@ovirt.org
>>> http://lists.ovirt.org/mailman/listinfo/users
>>>
>>>
>>
>> ___
>> Users mailing list
>> Users@ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/users
>>
>>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[Donny Davis]

Yaniv,

If there was a central logging server, would the hypervisors send them
there and stop writing to disk (given its setup properly), or does it write
them anyway?


https://www.ovirt.org/documentation/admin-guide/chap-Log_Files/

On Thu, Jan 4, 2018 at 11:43 AM, Yaniv Kaul  wrote:

>
>
> On Thu, Jan 4, 2018 at 5:04 PM, Donny Davis  wrote:
>
>> That makes more sense. Have you measured the write load on the disks from
>> just the hypervisor processes. I have included a screen shot from mine, and
>> the load is very low in the Kilobytes/sec
>>
>
> And those are probably the logs, which will be written anyway...
> Y.
>
>
>>
>> I am not sure of the implications of changing these parameters, and I do
>> not see an perceivable benefits from doing so.
>>
>> [image: Inline image 1]
>>
>> On Thu, Jan 4, 2018 at 9:51 AM, andreil1  wrote:
>>
>>>
>>>
>>> On 4 Jan 2018, at 14:52, Donny Davis  wrote:
>>>
>>> What is the purpose in putting these directives in for the hypervisor?
>>>
>>>
>>> I have small node where system and data domains located on the same RAID.
>>> Data domains are on separate partitions.
>>> These options allow minimise disk access activity.
>>>
>>>
>>> On Thu, Jan 4, 2018 at 6:46 AM, andreil1  wrote:
>>>
 Hi !

 Is it safe to turn on these options (noatime, nodiratime) in oVirt node
 fstab for these mount points?
 /home
 /
 /tmp
 /var
 /var/log
 /var/log/audit

 Node 4.2 installed on CentOS, not with node DVD.

 Thanks.

 ___
 Users mailing list
 Users@ovirt.org
 http://lists.ovirt.org/mailman/listinfo/users

>>>
>>>
>>>
>>> ___
>>> Users mailing list
>>> Users@ovirt.org
>>> http://lists.ovirt.org/mailman/listinfo/users
>>>
>>>
>>
>> ___
>> Users mailing list
>> Users@ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/users
>>
>>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[Yaniv Kaul]

On Thu, Jan 4, 2018 at 5:04 PM, Donny Davis  wrote:

> That makes more sense. Have you measured the write load on the disks from
> just the hypervisor processes. I have included a screen shot from mine, and
> the load is very low in the Kilobytes/sec
>

And those are probably the logs, which will be written anyway...
Y.


>
> I am not sure of the implications of changing these parameters, and I do
> not see an perceivable benefits from doing so.
>
> [image: Inline image 1]
>
> On Thu, Jan 4, 2018 at 9:51 AM, andreil1  wrote:
>
>>
>>
>> On 4 Jan 2018, at 14:52, Donny Davis  wrote:
>>
>> What is the purpose in putting these directives in for the hypervisor?
>>
>>
>> I have small node where system and data domains located on the same RAID.
>> Data domains are on separate partitions.
>> These options allow minimise disk access activity.
>>
>>
>> On Thu, Jan 4, 2018 at 6:46 AM, andreil1  wrote:
>>
>>> Hi !
>>>
>>> Is it safe to turn on these options (noatime, nodiratime) in oVirt node
>>> fstab for these mount points?
>>> /home
>>> /
>>> /tmp
>>> /var
>>> /var/log
>>> /var/log/audit
>>>
>>> Node 4.2 installed on CentOS, not with node DVD.
>>>
>>> Thanks.
>>>
>>> ___
>>> Users mailing list
>>> Users@ovirt.org
>>> http://lists.ovirt.org/mailman/listinfo/users
>>>
>>
>>
>>
>> ___
>> Users mailing list
>> Users@ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/users
>>
>>
>
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[Yaniv Kaul]

On Thu, Jan 4, 2018 at 1:45 PM, Service  wrote:

> Hi !
>
> Is it safe to turn on these options (noatime, nodiratime) in oVirt node
> fstab for these mount points?
>

Not sure, but why would you do that?
Y.


> /home
> /
> /tmp
> /var
> /var/log
> /var/log/audit
>
> Node 4.2 installed on CentOS, not with node DVD.
>
> Thanks.
>
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[Fabrice Bacchella]

Both are no brainer to activate (noatime is a superset of nodiratime, see 
https://lwn.net/Articles/244941/) for every mount point, unless you really know 
why you need exact atime.

If you want to be super-safe, use relatime. You will get not-exact but usable 
atime, to know if a file was acceded after write.

More informations:
https://en.wikipedia.org/wiki/Stat_(system_call)#Criticism_of_atime


> Le 4 janv. 2018 à 12:46, andreil1  a écrit :
> 
> Hi !
> 
> Is it safe to turn on these options (noatime, nodiratime) in oVirt node fstab 
> for these mount points?
> /home
> /
> /tmp
> /var
> /var/log
> /var/log/audit
> 
> Node 4.2 installed on CentOS, not with node DVD.
> 
> Thanks.
> 
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users

___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[Donny Davis]

That makes more sense. Have you measured the write load on the disks from
just the hypervisor processes. I have included a screen shot from mine, and
the load is very low in the Kilobytes/sec

I am not sure of the implications of changing these parameters, and I do
not see an perceivable benefits from doing so.

[image: Inline image 1]

On Thu, Jan 4, 2018 at 9:51 AM, andreil1  wrote:

>
>
> On 4 Jan 2018, at 14:52, Donny Davis  wrote:
>
> What is the purpose in putting these directives in for the hypervisor?
>
>
> I have small node where system and data domains located on the same RAID.
> Data domains are on separate partitions.
> These options allow minimise disk access activity.
>
>
> On Thu, Jan 4, 2018 at 6:46 AM, andreil1  wrote:
>
>> Hi !
>>
>> Is it safe to turn on these options (noatime, nodiratime) in oVirt node
>> fstab for these mount points?
>> /home
>> /
>> /tmp
>> /var
>> /var/log
>> /var/log/audit
>>
>> Node 4.2 installed on CentOS, not with node DVD.
>>
>> Thanks.
>>
>> ___
>> Users mailing list
>> Users@ovirt.org
>> http://lists.ovirt.org/mailman/listinfo/users
>>
>
>
>
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[andreil1]

> On 4 Jan 2018, at 14:52, Donny Davis  > wrote:
> 
> What is the purpose in putting these directives in for the hypervisor?

I have small node where system and data domains located on the same RAID.
Data domains are on separate partitions.
These options allow minimise disk access activity.

> 
> On Thu, Jan 4, 2018 at 6:46 AM, andreil1  > wrote:
> Hi !
> 
> Is it safe to turn on these options (noatime, nodiratime) in oVirt node fstab 
> for these mount points?
> /home
> /
> /tmp
> /var
> /var/log
> /var/log/audit
> 
> Node 4.2 installed on CentOS, not with node DVD.
> 
> Thanks.
> 
> ___
> Users mailing list
> Users@ovirt.org 
> http://lists.ovirt.org/mailman/listinfo/users 
> 
> 

___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users

Re: [ovirt-users] Q: ext4 noatime/nidiratime for oVirt node mount points

[Donny Davis]

What is the purpose in putting these directives in for the hypervisor?

On Thu, Jan 4, 2018 at 6:46 AM, andreil1  wrote:

> Hi !
>
> Is it safe to turn on these options (noatime, nodiratime) in oVirt node
> fstab for these mount points?
> /home
> /
> /tmp
> /var
> /var/log
> /var/log/audit
>
> Node 4.2 installed on CentOS, not with node DVD.
>
> Thanks.
>
> ___
> Users mailing list
> Users@ovirt.org
> http://lists.ovirt.org/mailman/listinfo/users
>
___
Users mailing list
Users@ovirt.org
http://lists.ovirt.org/mailman/listinfo/users