My DB doesn't have a specific partition anywhere, but there's still a
symlink for it to the data partition. On my home cluster with all DB, WAL,
and Data on the same disk without any partitions specified there is a block
symlink but no block.wal symlink.
For the cluster with a specific WAL partition, but no DB partition, my OSD
paths looks like [1] this. For my cluster with everything on the same
disk, my OSD paths look like [2] this. Unless you have a specific path for
"bluefs_wal_partition_path" then it's going to find itself on the same
partition as the db.
[1] $ ceph osd metadata 5 | grep path
"bluefs_db_partition_path": "/dev/dm-29",
"bluefs_wal_partition_path": "/dev/dm-41",
"bluestore_bdev_partition_path": "/dev/dm-29",
[2] $ ceph osd metadata 5 | grep path
"bluefs_db_partition_path": "/dev/dm-5",
"bluestore_bdev_partition_path": "/dev/dm-5",
On Mon, Oct 22, 2018 at 4:21 PM Robert Stanford <rstanford8...@gmail.com>
wrote:
>
> Let me add, I have no block.wal file (which the docs suggest should be
> there).
> http://docs.ceph.com/docs/master/rados/configuration/bluestore-config-ref/
>
> On Mon, Oct 22, 2018 at 3:13 PM Robert Stanford <rstanford8...@gmail.com>
> wrote:
>
>>
>> We're out of sync, I think. You have your DB on your data disk so your
>> block.db symlink points to that disk, right? There is however no wal
>> symlink? So how would you verify your WAL actually lived on your NVMe?
>>
>> On Mon, Oct 22, 2018 at 3:07 PM David Turner <drakonst...@gmail.com>
>> wrote:
>>
>>> And by the data disk I mean that I didn't specify a location for the DB
>>> partition.
>>>
>>> On Mon, Oct 22, 2018 at 4:06 PM David Turner <drakonst...@gmail.com>
>>> wrote:
>>>
>>>> Track down where it says they point to? Does it match what you
>>>> expect? It does for me. I have my DB on my data disk and my WAL on a
>>>> separate NVMe.
>>>>
>>>> On Mon, Oct 22, 2018 at 3:21 PM Robert Stanford <
>>>> rstanford8...@gmail.com> wrote:
>>>>
>>>>>
>>>>> David - is it ensured that wal and db both live where the symlink
>>>>> block.db points? I assumed that was a symlink for the db, but necessarily
>>>>> for the wal, because it can live in a place different than the db.
>>>>>
>>>>> On Mon, Oct 22, 2018 at 2:18 PM David Turner <drakonst...@gmail.com>
>>>>> wrote:
>>>>>
>>>>>> You can always just go to /var/lib/ceph/osd/ceph-{osd-num}/ and look
>>>>>> at where the symlinks for block and block.wal point to.
>>>>>>
>>>>>> On Mon, Oct 22, 2018 at 12:29 PM Robert Stanford <
>>>>>> rstanford8...@gmail.com> wrote:
>>>>>>
>>>>>>>
>>>>>>> That's what they say, however I did exactly this and my cluster
>>>>>>> utilization is higher than the total pool utilization by about the
>>>>>>> number
>>>>>>> of OSDs * wal size. I want to verify that the wal is on the SSDs too
>>>>>>> but
>>>>>>> I've asked here and no one seems to know a way to verify this. Do you?
>>>>>>>
>>>>>>> Thank you, R
>>>>>>>
>>>>>>> On Mon, Oct 22, 2018 at 5:22 AM Maged Mokhtar <mmokh...@petasan.org>
>>>>>>> wrote:
>>>>>>>
>>>>>>>>
>>>>>>>> If you specify a db on ssd and data on hdd and not explicitly
>>>>>>>> specify a
>>>>>>>> device for wal, wal will be placed on same ssd partition with db.
>>>>>>>> Placing only wal on ssd or creating separate devices for wal and db
>>>>>>>> are
>>>>>>>> less common setups.
>>>>>>>>
>>>>>>>> /Maged
>>>>>>>>
>>>>>>>> On 22/10/18 09:03, Fyodor Ustinov wrote:
>>>>>>>> > Hi!
>>>>>>>> >
>>>>>>>> > For sharing SSD between WAL and DB what should be placed on SSD?
>>>>>>>> WAL or DB?
>>>>>>>> >
>>>>>>>> > ----- Original Message -----
>>>>>>>> > From: "Maged Mokhtar" <mmokh...@petasan.org>
>>>>>>>> > To: "ceph-users" <ceph-users@lists.ceph.com>
>>>>>>>> > Sent: Saturday, 20 October, 2018 20:05:44
>>>>>>>> > Subject: Re: [ceph-users] Drive for Wal and Db
>>>>>>>> >
>>>>>>>> > On 20/10/18 18:57, Robert Stanford wrote:
>>>>>>>> >
>>>>>>>> >
>>>>>>>> >
>>>>>>>> >
>>>>>>>> > Our OSDs are BlueStore and are on regular hard drives. Each OSD
>>>>>>>> has a partition on an SSD for its DB. Wal is on the regular hard
>>>>>>>> drives.
>>>>>>>> Should I move the wal to share the SSD with the DB?
>>>>>>>> >
>>>>>>>> > Regards
>>>>>>>> > R
>>>>>>>> >
>>>>>>>> >
>>>>>>>> > _______________________________________________
>>>>>>>> > ceph-users mailing list [ mailto:ceph-users@lists.ceph.com |
>>>>>>>> ceph-users@lists.ceph.com ] [
>>>>>>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com |
>>>>>>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com ]
>>>>>>>> >
>>>>>>>> > you should put wal on the faster device, wal and db could share
>>>>>>>> the same ssd partition,
>>>>>>>> >
>>>>>>>> > Maged
>>>>>>>> >
>>>>>>>> > _______________________________________________
>>>>>>>> > ceph-users mailing list
>>>>>>>> > ceph-users@lists.ceph.com
>>>>>>>> > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
>>>>>>>> > _______________________________________________
>>>>>>>> > ceph-users mailing list
>>>>>>>> > ceph-users@lists.ceph.com
>>>>>>>> > http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
>>>>>>>>
>>>>>>>> _______________________________________________
>>>>>>>> ceph-users mailing list
>>>>>>>> ceph-users@lists.ceph.com
>>>>>>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
>>>>>>>>
>>>>>>> _______________________________________________
>>>>>>> ceph-users mailing list
>>>>>>> ceph-users@lists.ceph.com
>>>>>>> http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
>>>>>>>
>>>>>>
_______________________________________________
ceph-users mailing list
ceph-users@lists.ceph.com
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
