bigger rootfs size

[nextgen-networks]

My system:
Banana Pi BPI-R4 on OpenWRT Snapshot builds

I've a 64 GB SDCard as system device.
Partition 7 (overlay) is expanded to maximum remaining space after initial install (58 GB - with cfdisk)

I found your script very useful as I do often upgrades to latest builds via https://firmware-selector.openwrt.org/

Was a bit puzzled if the partition size will be kept and therefore added the rootfs size to the upgrade/install script:
owut install --rootfs-size 57000
This throws an error
ERROR: 57000 above upper bound 1024

Is it possible to increase the maximum root partition size?

Thanks for your great work on owut!

[efahl]

Thanks, I was wondering how long it would take for someone to ask this. Apparently not very long! I'm going to write an FAQ, and your question will be "First!" Anyhow, the answer to your question is...

The upper bound is dictated by the ASU server for practical reasons. The way the partitions are created on some devices requires that the full-sized image be created and then compressed, which takes both a lot of RAM, disk and time.

As a test, I just did a couple of imagebuilder runs with rootfs partitions of 10000 and 20000 to see how long they would take (I copied my previous results from the PR when the limit was raised to 1024, openwrt/asu#827):

ROOTFS_PARTSIZE=	real	user	img size
104	26s	18s	12M
512	48s	25s	13M
1024	74s	33s	13M
10000	11m47s	4m36s	32M
20000	28m15s	13m9s	32M

Those last two rows should make fairly clear why increasing the upper limit is infeasible, until such time as the build process is reworked to reduce the time required to create larger images.

Note: the above tests were all run on an AMD R9 7950x 5.8GHz CPU with 64GB CL6000 RAM and PCIe 4 SSD, which is generally 3x faster than the ASU server hardware, so these numbers are well below what you'd see if using ASU server.