Block size vs disk type

[wsh303]

TL;DR

Default block size is bad for HDD performance

Expected Behavior

CryFS detects disk type on which vault is being created and/or:

1. Set larger block size for HDDs (512KB works nice for me)
2. Display warning message that default block size is bad for HDD performance

Actual Behavior

I tried to set up encrypted backup on external, USB3 connected HDD. By default CryFS uses 16KB block size, which is nice for SSDs but good, old HDDs don't like to work with lots of small files. Copy throughput for this block size is very low. So low that CryFS often crashes during data copy. Creating a vault using larger block sizes fixes performance and crash issues.

Steps to Reproduce the Problem

1. Create vault on HDD using default settings
2. Copy few GB of data to the vault

Specifications

• CryFS Version: 0.11.4
• Operating System (incl. Version): Windows 11