Skip to content

Latest commit

 

History

History
58 lines (43 loc) · 2.41 KB

disk-options.md

File metadata and controls

58 lines (43 loc) · 2.41 KB
Raw

Overview

Next

Disk options

After selecting your OS, you need to select some type of Disk where it will be installed.

Each VM comes with a single root peristent disk because you are choosing

A base image is loaded onto root disk during first boot

  • Bootable: you can attach to a VM
  • Durable: can survive VM terminate

Persistent Disks

Persistent disks are

  • Attached to the VM through the Network Interface. This is network storage appearing as a block device

  • Durable: Can survive VM terminate

  • Bootable: You can attach to a VM

  • Snapshots: incremental backups

  • Performance: Scales with size

  • HDD (cheaper; magnetic;) or SSD (faster; solid-state)

  • Dynamically resize

  • Can be attached in read-only mode to multiple VMs (allows you to share static data between instances, which is cheaper than replicating data to unique disks)

  • Zonal PD or Regional (synchronously replicated; active-active disk replication across 2 zones; high-availability;) - pd-standard (backed by HDD) - pd-balanced (backed by SSD; Balance performance and cost) - pd-ssd (backed by SSD)

  • All data at rest is encrypted

Local SSD disks

  • Physically attached to the VM
  • Ephemeral
  • High iops and low latency
  • Attach up to 8 Local SSD with 375GB max per disk for a total of 3TB
  • Data doesnt survive an instance stop / terminate, but can survive instance reset.
  • Cannot be reattached to a different VM

RAM Disk

  • Highest performance
  • Use tmpfs for in memory data storage of small data structures. It's recommended to use high memory VM if you need to take advantage of such features Along with a PD to backup the RAM data
  • Volatile/ Ephemeral: erase on stop/restart
  • Low latency and Low risk of data loss
  • Faster than Local disk; Slower than memory
    • Use when your application expects a file system structure and cannot directly store its data in memory
    • Fast cache / scratch disk

Shared core: Max 16 disk

Standard, High mem, High CPU, Memory optimized, Compute optimized - 128 disk

Note : All your disk share the same network throughput as the rest of your egress / ingress traffic. If you attach a lot of disks because of higher iops keep this in mind

Traditional Hardware disks vs Cloud Persistent Disk