Closed dduportal closed 1 year ago
A word on the pricing:
The HDD costs us, currently, around $4 per month: $3.01 + ~1$ per month of transactions
Switching to Standard SSD should increase slighlty: baseline of $4.80 (64 Gb, in the E6 category) + eventual transactions (limited to ~$12 monthly), same IOPS and bandwidth, and $0.47 per mount
Switching to Premium SSD should increase a bit more: baseline of $10 (64 Gb, in the P6 category), lower IOPS (250) and bandwidth (50 Mbits/s) but no transaction variable part, and still $0.47 per mount
Current cost for ci.jenkins.io storage for the past 6 month, to have an order of magnitude:
![Uploading Capture d’écran 2023-04-19 à 19.50.22.png…]()
Let's go for a Standard SSD \o/
20230419-helpdesk-3526
)Standard SSD' with a size of
64Gb` (category E6)back to work ✅
=> let's check the metrics in ~24h
This change did not had any visible effect except the Azure Advisor does not alert us on the VM anymore :'(
root@ci:~# lsblk /dev/sdc
NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
sdc 8:32 0 64G 0 disk
├─sdc1 8:33 0 49.9G 0 part /
├─sdc14 8:46 0 4M 0 part
└─sdc15 8:47 0 106M 0 part /boot/efi
root@ci:~# fdisk -l /dev/sdc
GPT PMBR size mismatch (104857599 != 134217727) will be corrected by w(rite).
Disk /dev/sdc: 64 GiB, 68719476736 bytes, 134217728 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: F9A32187-D01B-465B-AEC5-3D0FE6FADD47
Device Start End Sectors Size Type
/dev/sdc1 227328 104857566 104630239 49.9G Linux filesystem
/dev/sdc14 2048 10239 8192 4M BIOS boot
/dev/sdc15 10240 227327 217088 106M EFI System
Partition table entries are not in disk order.
=> the partition table seems in weird shape, which could explain a lot. => Please note the VM generation is v1 which could also have an impact (because not an UEFI boot as per https://learn.microsoft.com/en-us/azure/virtual-machines/generation-2)
Closing in favor of https://github.com/jenkins-infra/helpdesk/issues/3535
As per the Azure Advisor Monitor, we should switch the system disk of ci.jenkins.io to an SSD.
The VM has 2 disks today:
500 IOPS, 60 Mbit/s
) :JENKINS_HOME
of ci.jenkins.io is stored on a data disk (Premium SSD, hardware encrypted, 500Gb,P20 - 2300 IOPS, 150 MBps
)=> The Azure metrics (ref. https://learn.microsoft.com/en-us/azure/virtual-machines/disks-metrics) shown above does not show any contention on the system disk in the past 7 days, which does not prompt us to switch to an SSD. => However, the datadog VM metrics shows that the latency is clearly higher (
/dev/sdc
is the system disk,/dev/sdb
is the Premium SSD datadisk) which is a good reason to follow the advisor message:=> Please note that the system disk hosts the system, but also the temp dirs and the logs (along with all the container overlays).