> Sorry to mention this low-tech solution, but for
> really large BLOBs I still prefer storing only an
> UUID in the database and have file named with this
> UUID for BLOB storage.

My testing show, that blob transfer via local network interface
(Windows 2000, 1GHz, 512 MB RAM, IDE HDD, FB 1.0.3, JayBird) gives
performance ~4.5 MB/s. Transfer of same amount of data over 100 MBit
Ethernet network (server: Linux, 750 MHz, 512 MB RAM, SCSI HDD, FB
1.0.3) gives ~2.5 MB/s (for comparison, ftp to that host gives me 1.5
MB/s). HDD/RAM transfer rate on that server gives ~11 MB/s.

For me this means, that if you have to serve big files, you'd better
serve them from disk directly. But if your data are less than 1 MB
size, you're still under 1 sec. response time (in my case I keep
serialized Java classes, relatively small, avg. load time is 8 ms).

Unfortunatelly I cannot tell performance of embedded version of
Firebird, but probably with release of type 2 JDBC driver we will have
more exact data (preliminary results show ~2 times performance boost).

Best regards,
Roman Rokytskyy