[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Cloud-init delay - sometimes



On Tue, Sep 28, 2021 at 09:02:31PM +0200, Dick Visser wrote:
> Begin: Running /scripts/local-premount ... done.
> Begin: Will now check root file system ... fsck from util-linux 2.36.1
> [/sbin/fsck.ext4 (1) -- /dev/nvme0n1p1] fsck.ext4 -a -C0 /dev/nvme0n1p1
> /dev/nvme0n1p1: clean, 35442/516096 files, 242371/2064379 blocks
> done.
> [    9.042449] EXT4-fs (nvme0n1p1): mounted filesystem with ordered
> data mode. Opts: (null)
> done.
> Begin: Running /scripts/local-bottom ... [   28.809447]  nvme0n1: p1 p14 p15
> GROWROOT: CHANGED: partition=1 start=262144 old:[   28.819359]
> nvme0n1: p1 p14 p15
>  size=16515039 end=16777183 new: size=41680863 end=41943007
> [   40.228970] EXT4-fs (nvme0n1p1): mounted filesystem with ordered
> data mode. Opts: (null)
> done.
> Begin: Running /scripts/init-bottom ... done.
> [   40.258874] Not activating Mandatory Access Control as
> /sbin/tomoyo-init does not exist.
> [   40.359770] systemd[1]: Inserted module 'autofs4'

That looks like unusually slow IO for some reason.

Do you see reduced IO performance once the instance has finished
booting, or is it only during the early boot period?

Is there any correlation between availability zone and slow launches?
Are they all clustered in one AZ?

Assuming your EBS volumes are the gp2 type, it may be worth checking
their BurstBalance metric.  It seems unlikely that you'd be getting
throttled on only ~10% of your launches, though, if that was it.  See
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-volume-types.html#EBSVolumeTypes_gp2
and
https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-io-characteristics.html#ebs-io-metrics
for some details on the IO performance properties of EBS.

noah

Attachment: signature.asc
Description: PGP signature


Reply to: