That's what I mean, the number of writing, but has to be to the same location.

The GDBM uses default allocation unit size as the hash table(bucket) size, normally it's 32k on a SDHC card.

Each data item uses about 12 bytes, so each bucket contains about 3000 entries. For every entry update it writes disk to sync it, so it writes about 3000 times to one block just to fill it. Sounds like a killing machine to SD card.

syzygy, I am glad you even make the repository smaller. Honestly I didn't dig deep into the detail implementation of the gdbm. It's a very old piece of junk. I can't find even a working version on Windows platform, none works actually. I ported it to Windows but didn't do any clean up. Time to move on to rid of it.