I have my dashboards and I can see that the db nvmes are always running on 100% utilization (you can monitor with iostat -x 1) and it generates all the time iowaits which is between 1-3. I’m using nvme in front of the ssds. Istvan Szabo Senior Infrastructure Engineer --------------------------------------------------- Agoda Services Co., Ltd. e: istvan.szabo@xxxxxxxxx<mailto:istvan.szabo@xxxxxxxxx> --------------------------------------------------- From: Victor Hooi <victorhooi@xxxxxxxxx> Sent: Friday, October 1, 2021 5:30 AM To: Eugen Block <eblock@xxxxxx> Cc: Szabo, Istvan (Agoda) <Istvan.Szabo@xxxxxxxxx>; 胡 玮文 <huww98@xxxxxxxxxxx>; ceph-users <ceph-users@xxxxxxx> Subject: Re: Re: is it possible to remove the db+wal from an external device (nvme) Email received from the internet. If in doubt, don't click any link nor open any attachment ! ________________________________ Hi, I'm curious - how did you tell that the separate WAL+DB volume was slowing things down? I assume you did some benchmarking - is there any chance you'd be willing to share results? (Or anybody else that's been in a similar situation). What sorts of devices are you using for the WAL+DB, versus the data disks? We're using NAND SSDs, with Optanes for the WAL+DB, and on some systems I am seeing slowly than expected behaviour - need to dive deeper into it In my case, I was running with 4 or 2 OSDs per Optane volume: https://www.reddit.com/r/ceph/comments/k2lef1/how_many_waldb_partitions_can_you_run_per_optane/ but I couldn't seem to get the results I'd expected - so curious what people are seeing in the real world - and of course, we might need to follow the steps here to remove them as well. Thanks, Victor On Thu, 30 Sept 2021 at 16:10, Eugen Block <eblock@xxxxxx<mailto:eblock@xxxxxx>> wrote: Yes, I believe for you it should work without containers although I haven't tried the migrate command in a non-containerized cluster yet. But I believe this is a general issue for containerized clusters with regards to maintenance. I haven't checked yet if there are existing tracker issues for this, but maybe this should be worth creating one? Zitat von "Szabo, Istvan (Agoda)" <Istvan.Szabo@xxxxxxxxx<mailto:Istvan.Szabo@xxxxxxxxx>>: > Actually I don't have containerized deployment, my is normal one. So > it should work the lvm migrate. > > Istvan Szabo > Senior Infrastructure Engineer > --------------------------------------------------- > Agoda Services Co., Ltd. > e: istvan.szabo@xxxxxxxxx<mailto:istvan.szabo@xxxxxxxxx> > --------------------------------------------------- > > -----Original Message----- > From: Eugen Block <eblock@xxxxxx<mailto:eblock@xxxxxx>> > Sent: Wednesday, September 29, 2021 8:49 PM > To: 胡 玮文 <huww98@xxxxxxxxxxx<mailto:huww98@xxxxxxxxxxx>> > Cc: Igor Fedotov <ifedotov@xxxxxxx<mailto:ifedotov@xxxxxxx>>; Szabo, Istvan (Agoda) > <Istvan.Szabo@xxxxxxxxx<mailto:Istvan.Szabo@xxxxxxxxx>>; ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx> > Subject: Re: is it possible to remove the db+wal from an external > device (nvme) > > Email received from the internet. If in doubt, don't click any link > nor open any attachment ! > ________________________________ > > That's what I did and pasted the results in my previous comments. > > > Zitat von 胡 玮文 <huww98@xxxxxxxxxxx<mailto:huww98@xxxxxxxxxxx>>: > >> Yes. And “cephadm shell” command does not depend on the running >> daemon, it will start a new container. So I think it is perfectly fine >> to stop the OSD first then run the “cephadm shell” command, and run >> ceph-volume in the new shell. >> >> 发件人: Eugen Block<mailto:eblock@xxxxxx<mailto:eblock@xxxxxx>> >> 发送时间: 2021年9月29日 21:40 >> 收件人: 胡 玮文<mailto:huww98@xxxxxxxxxxx<mailto:huww98@xxxxxxxxxxx>> >> 抄送: Igor Fedotov<mailto:ifedotov@xxxxxxx<mailto:ifedotov@xxxxxxx>>; Szabo, Istvan >> (Agoda)<mailto:Istvan.Szabo@xxxxxxxxx<mailto:Istvan.Szabo@xxxxxxxxx>>; >> ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx><mailto:ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx>> >> 主题: Re: is it possible to remove the db+wal from an external device >> (nvme) >> >> The OSD has to be stopped in order to migrate DB/WAL, it can't be done >> live. ceph-volume requires a lock on the device. >> >> >> Zitat von 胡 玮文 <huww98@xxxxxxxxxxx<mailto:huww98@xxxxxxxxxxx>>: >> >>> I’ve not tried it, but how about: >>> >>> cephadm shell -n osd.0 >>> >>> then run “ceph-volume” commands in the newly opened shell. The >>> directory structure seems fine. >>> >>> $ sudo cephadm shell -n osd.0 >>> Inferring fsid e88d509a-f6fc-11ea-b25d-a0423f3ac864 >>> Inferring config >>> /var/lib/ceph/e88d509a-f6fc-11ea-b25d-a0423f3ac864/osd.0/config >>> Using recent ceph image >>> cr.example.com/infra/ceph@sha256:8a0f6f285edcd6488e2c91d3f9fa43534d37<http://cr.example.com/infra/ceph@sha256:8a0f6f285edcd6488e2c91d3f9fa43534d37> >>> d7a9b37db1e0ff6691aae6466530 root@host0:/# ll >>> /var/lib/ceph/osd/ceph-0/ total 68 >>> drwx------ 2 ceph ceph 4096 Sep 20 04:15 ./ >>> drwxr-x--- 1 ceph ceph 4096 Sep 29 13:32 ../ >>> lrwxrwxrwx 1 ceph ceph 24 Sep 20 04:15 block -> /dev/ceph-hdd/osd.0.data >>> lrwxrwxrwx 1 ceph ceph 23 Sep 20 04:15 block.db -> >>> /dev/ubuntu-vg/osd.0.db >>> -rw------- 1 ceph ceph 37 Sep 20 04:15 ceph_fsid >>> -rw------- 1 ceph ceph 387 Jun 21 13:24 config >>> -rw------- 1 ceph ceph 37 Sep 20 04:15 fsid >>> -rw------- 1 ceph ceph 55 Sep 20 04:15 keyring >>> -rw------- 1 ceph ceph 6 Sep 20 04:15 ready >>> -rw------- 1 ceph ceph 3 Apr 2 01:46 require_osd_release >>> -rw------- 1 ceph ceph 10 Sep 20 04:15 type >>> -rw------- 1 ceph ceph 38 Sep 17 14:26 unit.configured >>> -rw------- 1 ceph ceph 48 Nov 9 2020 unit.created >>> -rw------- 1 ceph ceph 35 Sep 17 14:26 unit.image >>> -rw------- 1 ceph ceph 306 Sep 17 14:26 unit.meta >>> -rw------- 1 ceph ceph 1317 Sep 17 14:26 unit.poststop >>> -rw------- 1 ceph ceph 3021 Sep 17 14:26 unit.run >>> -rw------- 1 ceph ceph 142 Sep 17 14:26 unit.stop >>> -rw------- 1 ceph ceph 2 Sep 20 04:15 whoami >>> >>> 发件人: Eugen Block<mailto:eblock@xxxxxx<mailto:eblock@xxxxxx>> >>> 发送时间: 2021年9月29日 21:29 >>> 收件人: Igor Fedotov<mailto:ifedotov@xxxxxxx<mailto:ifedotov@xxxxxxx>> >>> 抄送: 胡 玮文<mailto:huww98@xxxxxxxxxxx<mailto:huww98@xxxxxxxxxxx>>; Szabo, Istvan >>> (Agoda)<mailto:Istvan.Szabo@xxxxxxxxx<mailto:Istvan.Szabo@xxxxxxxxx>>; >>> ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx><mailto:ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx>> >>> 主题: Re: Re: 回复: [ceph-users] Re: is it possible to >>> remove the db+wal from an external device (nvme) >>> >>> Hi Igor, >>> >>> thanks for your input. I haven't done this in a prod env yet either, >>> still playing around in a virtual lab env. >>> I tried the symlink suggestion but it's not that easy, because it >>> looks different underneath the ceph directory than ceph-volume >>> expects it. These are the services underneath: >>> >>> ses7-host1:~ # ll /var/lib/ceph/152fd738-01bc-11ec-a7fd-fa163e672db2/ >>> insgesamt 48 >>> drwx------ 3 root root 4096 16. Sep 16:11 alertmanager.ses7-host1 >>> drwx------ 3 ceph ceph 4096 29. Sep 09:03 crash >>> drwx------ 2 ceph ceph 4096 16. Sep 16:39 crash.ses7-host1 >>> drwx------ 4 messagebus lp 4096 16. Sep 16:23 grafana.ses7-host1 >>> drw-rw---- 2 root root 4096 24. Aug 10:00 home >>> drwx------ 2 ceph ceph 4096 16. Sep 16:37 mgr.ses7-host1.wmgyit >>> drwx------ 3 ceph ceph 4096 16. Sep 16:37 mon.ses7-host1 >>> drwx------ 2 nobody nobody 4096 16. Sep 16:37 node-exporter.ses7-host1 >>> drwx------ 2 ceph ceph 4096 29. Sep 08:43 osd.0 >>> drwx------ 2 ceph ceph 4096 29. Sep 15:11 osd.1 >>> drwx------ 4 root root 4096 16. Sep 16:12 prometheus.ses7-host1 >>> >>> >>> While the directory in a non-containerized deployment looks like this: >>> >>> nautilus:~ # ll /var/lib/ceph/osd/ceph-0/ insgesamt 24 lrwxrwxrwx 1 >>> ceph ceph 93 29. Sep 12:21 block -> >>> /dev/ceph-a6d78a29-637f-494b-a839-76251fcff67e/osd-block-39340a48-54b >>> 3-4689-9896-f54d005c535d >>> -rw------- 1 ceph ceph 37 29. Sep 12:21 ceph_fsid >>> -rw------- 1 ceph ceph 37 29. Sep 12:21 fsid >>> -rw------- 1 ceph ceph 55 29. Sep 12:21 keyring >>> -rw------- 1 ceph ceph 6 29. Sep 12:21 ready >>> -rw------- 1 ceph ceph 10 29. Sep 12:21 type >>> -rw------- 1 ceph ceph 2 29. Sep 12:21 whoami >>> >>> >>> But even if I create the symlink to the osd directory it fails >>> because I only have ceph-volume within the containers where the >>> symlink is not visible to cephadm. >>> >>> >>> ses7-host1:~ # ll /var/lib/ceph/osd/ceph-1 lrwxrwxrwx 1 root root 57 >>> 29. Sep 15:08 /var/lib/ceph/osd/ceph-1 -> >>> /var/lib/ceph/152fd738-01bc-11ec-a7fd-fa163e672db2/osd.1/ >>> >>> ses7-host1:~ # cephadm ceph-volume lvm migrate --osd-id 1 --osd-fsid >>> b4c772aa-07f8-483d-ae58-0ab97b8d0cc4 --from db --target >>> ceph-b1ddff4b-95e8-4b91-b451-a3ea35d16ec0/osd-block-b4c772aa-07f8-483 >>> d-ae58-0ab97b8d0cc4 Inferring fsid >>> 152fd738-01bc-11ec-a7fd-fa163e672db2 >>> [...] >>> /usr/bin/podman: stderr --> Migrate to existing, Source: >>> ['--devs-source', '/var/lib/ceph/osd/ceph-1/block.db'] Target: >>> /var/lib/ceph/osd/ceph-1/block >>> /usr/bin/podman: stderr stdout: inferring bluefs devices from >>> bluestore path >>> /usr/bin/podman: stderr stderr: can't migrate >>> /var/lib/ceph/osd/ceph-1/block.db, not a valid bluefs volume >>> /usr/bin/podman: stderr --> Failed to migrate device, error code:1 >>> /usr/bin/podman: stderr --> Undoing lv tag set >>> /usr/bin/podman: stderr Failed to migrate to : >>> ceph-b1ddff4b-95e8-4b91-b451-a3ea35d16ec0/osd-block-b4c772aa-07f8-483 >>> d-ae58-0ab97b8d0cc4 >>> Traceback (most recent call last): >>> File "/usr/sbin/cephadm", line 6225, in <module> >>> r = args.func() >>> File "/usr/sbin/cephadm", line 1363, in _infer_fsid >>> return func() >>> File "/usr/sbin/cephadm", line 1422, in _infer_image >>> return func() >>> File "/usr/sbin/cephadm", line 3687, in command_ceph_volume >>> out, err, code = call_throws(c.run_cmd(), >>> verbosity=CallVerbosity.VERBOSE) >>> File "/usr/sbin/cephadm", line 1101, in call_throws >>> raise RuntimeError('Failed command: %s' % ' '.join(command)) >>> [...] >>> >>> >>> I could install the package ceph-osd (where ceph-volume is packaged >>> in) but it's not available by default (as you see this is a SES 7 >>> environment). >>> >>> I'm not sure what the design is here, it feels like the ceph-volume >>> migrate command is not applicable to containers yet. >>> >>> Regards, >>> Eugen >>> >>> >>> Zitat von Igor Fedotov <ifedotov@xxxxxxx<mailto:ifedotov@xxxxxxx>>: >>> >>>> Hi Eugen, >>>> >>>> indeed this looks like an issue related to containerized deployment, >>>> "ceph-volume lvm migrate" expects osd folder to be under >>>> /var/lib/ceph/osd: >>>> >>>>> stderr: 2021-09-29T06:56:24.787+0000 7fde05b96180 -1 >>>>> bluestore(/var/lib/ceph/osd/ceph-1) _lock_fsid failed to lock >>>>> /var/lib/ceph/osd/ceph-1/fsid (is another ceph-osd still >>>>> running?)(11) Resource temporarily unavailable >>>> >>>> As a workaround you might want to try to create a symlink to your >>>> actual location before issuing the migrate command: >>>> /var/lib/ceph/osd -> >>>> /var/lib/ceph/152fd738-01bc-11ec-a7fd-fa163e672db2/ >>>> >>>> More complicated (and more general IMO) way would be to run the >>>> migrate command from within a container deployed similarly (i.e. >>>> with all the proper subfolder mappings) to ceph-osd one. Just >>>> speculating - not a big expert in containers and never tried that >>>> with properly deployed production cluster... >>>> >>>> >>>> Thanks, >>>> >>>> Igor >>>> >>>> On 9/29/2021 10:07 AM, Eugen Block wrote: >>>>> Hi, >>>>> >>>>> I just tried with 'ceph-volume lvm migrate' in Octopus but it >>>>> doesn't really work. I'm not sure if I'm missing something here, >>>>> but I believe it's again the already discussed containers issue. To >>>>> be able to run the command for an OSD the OSD has to be offline, >>>>> but then you don't have access to the block.db because the path is >>>>> different from outside the container: >>>>> >>>>> ---snip--- >>>>> [ceph: root@host1 /]# ceph-volume lvm migrate --osd-id 1 --osd-fsid >>>>> b4c772aa-07f8-483d-ae58-0ab97b8d0cc4 --from db --target >>>>> ceph-b1ddff4b-95e8-4b91-b451-a3ea35d16ec0/osd-block-b4c772aa-07f8-4 >>>>> 83d-ae58-0ab97b8d0cc4 --> Migrate to existing, Source: >>>>> ['--devs-source', '/var/lib/ceph/osd/ceph-1/block.db'] >>>>> Target: >>>>> /var/lib/ceph/osd/ceph-1/block >>>>> stdout: inferring bluefs devices from bluestore path >>>>> stderr: >>>>> /home/abuild/rpmbuild/BUILD/ceph-15.2.14-84-gb6e5642e260/src/os/blu >>>>> estore/BlueStore.cc: In function 'int >>>>> BlueStore::_mount_for_bluefs()' thread >>>>> 7fde05b96180 >>>>> time >>>>> 2021-09-29T06:56:24.790161+0000 >>>>> stderr: >>>>> /home/abuild/rpmbuild/BUILD/ceph-15.2.14-84-gb6e5642e260/src/os/blu >>>>> estore/BlueStore.cc: 6876: FAILED ceph_assert(r == >>>>> 0) >>>>> stderr: 2021-09-29T06:56:24.787+0000 7fde05b96180 -1 >>>>> bluestore(/var/lib/ceph/osd/ceph-1) _lock_fsid failed to lock >>>>> /var/lib/ceph/osd/ceph-1/fsid (is another ceph-osd still >>>>> running?)(11) Resource temporarily unavailable >>>>> >>>>> >>>>> # path outside >>>>> host1:~ # ll >>>>> /var/lib/ceph/152fd738-01bc-11ec-a7fd-fa163e672db2/osd.1/ >>>>> insgesamt 60 >>>>> lrwxrwxrwx 1 ceph ceph 93 29. Sep 08:43 block -> >>>>> /dev/ceph-b1ddff4b-95e8-4b91-b451-a3ea35d16ec0/osd-block-b4c772aa-07f8-483d-ae58-0ab97b8d0cc4 >>>>> lrwxrwxrwx 1 ceph ceph 90 29. Sep 08:43 block.db -> >>>>> /dev/ceph-6f1b8f49-daf2-4631-a2ef-12e9452b01ea/osd-db-69b11aa0-af96 >>>>> -443e-8f03-5afa5272131f >>>>> ---snip--- >>>>> >>>>> >>>>> But if I shutdown the OSD I can't access the block and block.db >>>>> devices. I'm not even sure how this is supposed to work with >>>>> cephadm. Maybe I'm misunderstanding, though. Or is there a way to >>>>> provide the offline block.db path to 'ceph-volume lvm migrate'? >>>>> >>>>> >>>>> >>>>> Zitat von 胡 玮文 <huww98@xxxxxxxxxxx<mailto:huww98@xxxxxxxxxxx>>: >>>>> >>>>>> You may need to use `ceph-volume lvm migrate’ [1] instead of >>>>>> ceph-bluestore-tool. If I recall correctly, this is a pretty new >>>>>> feature, I’m not sure whether it is available to your version. >>>>>> >>>>>> If you use ceph-bluestore-tool, then you need to modify the LVM >>>>>> tags manually. Please refer to the previous threads, e.g. [2] and >>>>>> some more. >>>>>> >>>>>> [1]: https://docs.ceph.com/en/latest/man/8/ceph-volume/#migrate >>>>>> [2]: >>>>>> https://lists.ceph.io/hyperkitty/list/ceph-users@xxxxxxx/thread/VX >>>>>> 23NQ66P3PPEX36T3PYYMHPLBSFLMYA/#JLNDFGXR4ZLY27DHD3RJTTZEDHRZJO4Q >>>>>> >>>>>> 发件人: Szabo, Istvan (Agoda)<mailto:Istvan.Szabo@xxxxxxxxx<mailto:Istvan.Szabo@xxxxxxxxx>> >>>>>> 发送时间: 2021年9月28日 18:20 >>>>>> 收件人: Eugen Block<mailto:eblock@xxxxxx<mailto:eblock@xxxxxx>>; >>>>>> ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx><mailto:ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx>> >>>>>> 主题: Re: is it possible to remove the db+wal from an >>>>>> external device (nvme) >>>>>> >>>>>> Gave a try of it, so all the 3 osds finally failed :/ Not sure >>>>>> what went wrong. >>>>>> >>>>>> Do the normal maintenance things, ceph osd set noout, ceph osd set >>>>>> norebalance, stop the osd and run this command: >>>>>> ceph-bluestore-tool bluefs-bdev-migrate --dev-target >>>>>> /var/lib/ceph/osd/ceph-0/block --devs-source >>>>>> /var/lib/ceph/osd/ceph-8/block.db --path /var/lib/ceph/osd/ceph-8/ >>>>>> Output: >>>>>> device removed:1 /var/lib/ceph/osd/ceph-8/block.db device added: 1 >>>>>> /dev/dm-2 >>>>>> >>>>>> When tried to start I got this in the log: >>>>>> osd.8 0 OSD:init: unable to mount object store >>>>>> ** ERROR: osd init failed: (13) Permission denied set uid:gid to >>>>>> 167:167 (ceph:ceph) ceph version 15.2.13 >>>>>> (c44bc49e7a57a87d84dfff2a077a2058aa2172e2) >>>>>> octopus (stable), process ceph-osd, pid 1512261 >>>>>> pidfile_write: ignore empty --pid-file >>>>>> >>>>>> From the another 2 osds the block.db removed and I can start it back. >>>>>> I've zapped the db drive just to be removed from the device >>>>>> completely and after machine restart none of these 2 osds came >>>>>> back, I guess missing the db device. >>>>>> >>>>>> Is there any steps missing? >>>>>> 1.Noout+norebalance >>>>>> 2. Stop osd >>>>>> 3. migrate with the above command the block.db to the block. >>>>>> 4. do on the other osds which is sharing the same db device that >>>>>> want to remove. >>>>>> 5. zap the db device >>>>>> 6. start back the osds. >>>>>> >>>>>> Istvan Szabo >>>>>> Senior Infrastructure Engineer >>>>>> --------------------------------------------------- >>>>>> Agoda Services Co., Ltd. >>>>>> e: istvan.szabo@xxxxxxxxx<mailto:istvan.szabo@xxxxxxxxx> >>>>>> --------------------------------------------------- >>>>>> >>>>>> -----Original Message----- >>>>>> From: Eugen Block <eblock@xxxxxx<mailto:eblock@xxxxxx>> >>>>>> Sent: Monday, September 27, 2021 7:42 PM >>>>>> To: ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx> >>>>>> Subject: Re: is it possible to remove the db+wal from >>>>>> an external device (nvme) >>>>>> >>>>>> Email received from the internet. If in doubt, don't click any >>>>>> link nor open any attachment ! >>>>>> ________________________________ >>>>>> >>>>>> Hi, >>>>>> >>>>>> I think 'ceph-bluestore-tool bluefs-bdev-migrate' could be of use >>>>>> here. I haven't tried it in a production environment yet, only in >>>>>> virtual labs. >>>>>> >>>>>> Regards, >>>>>> Eugen >>>>>> >>>>>> >>>>>> Zitat von "Szabo, Istvan (Agoda)" <Istvan.Szabo@xxxxxxxxx<mailto:Istvan.Szabo@xxxxxxxxx>>: >>>>>> >>>>>>> Hi, >>>>>>> >>>>>>> Seems like in our config the nvme device as a wal+db in front of >>>>>>> the ssd slowing down the ssds osds. >>>>>>> I'd like to avoid to rebuild all the osd-, is there a way somehow >>>>>>> migrate to the "slower device" the wal+db without reinstall? >>>>>>> >>>>>>> Ty >>>>>>> _______________________________________________ >>>>>>> ceph-users mailing list -- ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx> To unsubscribe send >>>>>>> an email to ceph-users-leave@xxxxxxx<mailto:ceph-users-leave@xxxxxxx> >>>>>> >>>>>> >>>>>> >>>>>> _______________________________________________ >>>>>> ceph-users mailing list -- ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx> To unsubscribe send >>>>>> an email to ceph-users-leave@xxxxxxx<mailto:ceph-users-leave@xxxxxxx> >>>>>> _______________________________________________ >>>>>> ceph-users mailing list -- ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx> To unsubscribe send >>>>>> an email to ceph-users-leave@xxxxxxx<mailto:ceph-users-leave@xxxxxxx> >>>>> >>>>> >>>>> >>>>> _______________________________________________ >>>>> ceph-users mailing list -- ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx> To unsubscribe send >>>>> an email to ceph-users-leave@xxxxxxx<mailto:ceph-users-leave@xxxxxxx> _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx<mailto:ceph-users@xxxxxxx> To unsubscribe send an email to ceph-users-leave@xxxxxxx<mailto:ceph-users-leave@xxxxxxx> _______________________________________________ ceph-users mailing list -- ceph-users@xxxxxxx To unsubscribe send an email to ceph-users-leave@xxxxxxx
 |