linux - Berkeley vs SQLite: RPM database after power loss -


i changed default rpm database berkeley on embedded x86 linux system running kernel v3.4.34 , rpm-5.4.9; whereas beforehand system running kernel 2.6.34 , rpm-5.1.9 , default rpm database sqlite. started seeing reports of rpm database failures in regards power pulls. wondering if experts on forum had data or recommendations in area of using berkeley on sqlite in regards system needs power loss tolerant?

in research have come across following manual pages: berkeley db recoverability

i found “berkeley db uses same techniques data integrity , failure recovery popular enterprise relational systems on market, , able provide same reliability guarantees. these services, including two-phase locking , write-ahead logging, allow berkeley db survive system failures without losing data. recovery processing @ system restart time ensures committed database updates restored , available, , interrupted work rolled not appear in database.”

if correct, issue experiencing interface between linux filesystem (ext4) , underlying storage hardware (emmc).

the emmc spec reads when operating in normal data reliability mode there risk written data may corrupted unforeseen events such power interruption. having said this, not quite sure if had been observing in testing. given equal conditions why sqlite come out better in respect?

yes: rpm-5.4.9 uses berkeley db transactions , should automate recovery (and discard uncommitted transactions) when rpmdb next reopened. isn't true if using rpm+sqlite. using bdb or sqlite? wish use bdb (recommended) or sqlite?

i don't entirely understand why believe there connection between ext4 , emmc? using flash memory? there's number of issues running rpm+bdb on emmc have been reported. reliability of bdb , emmc quite different, different solution paths.

i'm not sure asking "... sqlite come out better ..." because reliability of bdb vs sqlite different issue magnetic vs flash storage.


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