27.02.2015 15:18, Slavomir Skopalik wrote: > Hi, > I was investigate more about record storage and I found this: > If record going to be fragmented than each part are compressed > separatly.
Not exactly so. The big record is prepared for compression as a whole, then tail of record is packed and put at separate page(s) and finally what left (and could be put on single page) is really "re-compressed" separately. > And when record is materialized in RAM all parts are reads and decompress > separatly. What problem do you see here ? How else do you propose to decompress fragmented record ? > If comprossor cannot fit in small space, than rest of space is padded > (char 0x0 is in use). Record image in memory always have fixed length, according to record format. > This wastage CPU and disk space. CPU - yes, Memory - yes, Disk - no. Also, note, it allows later to not waste CPU when fields are accessed and record is updated, AFAIU. Regards, Vlad ------------------------------------------------------------------------------ Dive into the World of Parallel Programming The Go Parallel Website, sponsored by Intel and developed in partnership with Slashdot Media, is your hub for all things parallel software development, from weekly thought leadership blogs to news, videos, case studies, tutorials and more. Take a look and join the conversation now. http://goparallel.sourceforge.net/ Firebird-Devel mailing list, web interface at https://lists.sourceforge.net/lists/listinfo/firebird-devel
