03-13-2024, 08:41 PM
You're welcome. Right, it doesn't look possible to replace XZ with Zstandard for the main ISO and stay within the 700 MiB size limit. However, I think it is possible to replace lz4 with Zstandard for the low-compression ISO and preserve the USB/VM boot speed.
I have performed a rough benchmark to see if this is the case. For the benchmark, I used a VM (VirtualBox 7 on a Linux host) instead of a USB flash drive so USB transfer speed didn't cap the decompression speed. I put the ISOs on an NVMe drive and created a variant of the RC1 ISO with Zstandard SquashFS. To measure the approximate boot time, I started my phone's stopwatch when I reset the VM and stopped it when Conky appeared on the screen. When the boot menu came up, I quickly pressed Enter to skip it. Like I said, rough! :-)
Here are the results I got (in seconds):
It looks like lz4 and Zstandard are both so fast that other factors determine the boot time. The higher maximum possible decompression speed of lz4 doesn't seem to make a difference in this situation.
I have performed a rough benchmark to see if this is the case. For the benchmark, I used a VM (VirtualBox 7 on a Linux host) instead of a USB flash drive so USB transfer speed didn't cap the decompression speed. I put the ISOs on an NVMe drive and created a variant of the RC1 ISO with Zstandard SquashFS. To measure the approximate boot time, I started my phone's stopwatch when I reset the VM and stopped it when Conky appeared on the screen. When the boot menu came up, I quickly pressed Enter to skip it. Like I said, rough! :-)
Here are the results I got (in seconds):
- dsl-2024.rc1.iso (648M): 36, 37, 36
- dsl-2024.rc1.lz4.iso (1116M): 24, 23, 25
- dsl-2024.rc1.zst.iso (767M): 25, 25, 24
It looks like lz4 and Zstandard are both so fast that other factors determine the boot time. The higher maximum possible decompression speed of lz4 doesn't seem to make a difference in this situation.