SATA SSD seems to need 'spin up' time after being idle

[Chris Green <cl@isbd.net>]

I have a Fujitsu q957 system running Debian 13 that has two 2TB disk
drives, the main one is an NVME disk and the other is a SATA SSD (a
Crucial BX500 to be specific).

The SATA SSD seems to go to sleep after being idle for a while and
takes several seconds to wake up when it's accessed. Once woken up it
works fine with the expected speed etc.

Can anyone suggest why this start-up delay is happening and, more to
the point, how to stop it?

The fstab entry for the disk is:-

    UUID=7dde06f8-5179-4ec9-9def-59f68678e40c /xub ext4

... and fdisk reports:-

    Disk /dev/sda: 1.82 TiB, 2000398934016 bytes, 3907029168 sectors
    Disk model: CT2000BX500SSD1
    Units: sectors of 1 * 512 = 512 bytes
    Sector size (logical/physical): 512 bytes / 512 bytes
    I/O size (minimum/optimal): 512 bytes / 512 bytes
    Disklabel type: gpt
    Disk identifier: AF85EABA-F968-4A9E-97D2-5B12CF14E2F6

    Device     Start        End    Sectors  Size Type
    /dev/sda1   2048 3907028991 3907026944  1.8T Linux filesystem


-- 
Chris Green
·