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Re: commit: ldap/doc/man/man5 slapd-bdb.5

Hallvard B Furuseth wrote:
Howard Chu writes:
Besides, no worthwhile filesystems in common use today use 512 byte blocks.

Famous last words... Next FS revolutions will see - oh, blocks of blocks where the inner blocks often are small. Or whatever.

Heh. Total digression now. But no, not at all.

This isn't like saying "no one will ever need more than 640K." Historical trends shows that resource sizes only ever increase, never decrease. Storage densities increase, capacities increase, and the overhead of managing the storage increases. The only way to keep a handle on such large capacities is to use larger and larger allocation units. The hard drive industry has been trying to push for 4KB sectors as a standard for years, because the command overhead with 512 byte sectors is too high. The SSD industry is using flash memory devices with erase blocks at 128KB and growing.

Filesystem block sizes can only increase, to keep up, otherwise performance will be abysmal. The only thing to be afraid of here is that BDB's 64K limit may already be too small for a lot of common technologies today.
-- Howard Chu
CTO, Symas Corp. http://www.symas.com
Director, Highland Sun http://highlandsun.com/hyc/
Chief Architect, OpenLDAP http://www.openldap.org/project/