Resizing a volume
A mounted volume can be resized live, with no dismount and no interruption to open files. Select the volume and open Resize; the dialog shows current size and usage.
Growing always succeeds and takes effect immediately. Shrinking succeeds only while current usage fits the new size; a volume cannot be shrunk below its used space, so free data first if you need to shrink further. A process blocked because the volume was full resumes automatically shortly after a grow. If the volume is image-backed, the new size is recorded at the next save.
Because the volume is thin, it only consumes memory for the data it actually holds, and deleting files frees that memory. Resizing changes the logical capacity, not the memory in use. Grow to raise the ceiling when a volume is filling up; shrink to lower the maximum it may reach, for example to cap the RAM a volume is allowed to consume.