Hi,

Firebird version: LI-V6.2.908 Firebird 1.0 (classic-64)
OS: Linux/debian kernel 2.4.20
Filesystem: XFS

I am still struggling with continuous insert of large BLOBs into the
DB.
My DB has one main table:

CREATE TABLE VIDEO (
VIDEO_ID INTEGER NOT NULL
, SEQUENCE_ID INTEGER
, TS TIMESTAMP
, VIDEO_DATA BLOB( 65535, 0 )
, CONSTRAINT PK_VIDEO PRIMARY KEY ( VIDEO_ID )
)

One first process does the following continually:
- read data ftom a video device (e.g., /dev/video<x>) and insert a
new record into VIDEO as soon as 10MB where read from the device
- commit transaction after insert and


One second process executes the following every minute (setitimer):
- DELETE FROM VIDEO WHERE TS < :some_time
, where :some_time is calculated to be (say) current_timestamp - 60
minutes.
- Execute a SELECT COUNT(*) FROM VIDEO (Ivan explained that
counting rows could help touching deleted records)

Each process use one DB connection
Isolation level : read commited, rec version for all transaction
All transaction are short (commit after each SQL command)

Now the problem:
----------------

The size of the DB should be approximatively the size of a 60
minutes video (about 2GB), perhaps a little more. But it seems that
no garbage collection is done at all, since the DB size fills up all
my 20GB disk.
After some hours running the test, there is only 1 record left in
the DB (should be about 10MB), and however the disk is full (20GB)

Has someone any idea of what could be wrong?
How could I be sure, that every deleted record will effectively be
garbaged collected and its space freed for other inserts?

Any hint could really help,
Fabrice Aeschbacher

Here an output from gstat, as the disk was full (please not that
there is only 1 record left in the VIDEO table):

========= G S T A T ============================================
Database "video.gdb"

Database header page information:
Flags 0
Checksum 12345
Generation 7229
Page size 8192
ODS version 10.0
Oldest transaction 7184
Oldest active 7225
Oldest snapshot 7225
Next transaction 7226
Bumped transaction 1
Sequence number 0
Next attachment ID 0
Implementation ID 19
Shadow count 0
Page buffers 0
Next header page 0
Database dialect 3
Creation date May 20, 2003 17:49:33
Attributes

Variable header data:
Sweep interval: 1000
*END*


Database file sequence:
File video.gdb is the only file

Database log page information:
Creation date
Log flags: 2
No write ahead log

Next log page: 0

Variable log data:
Control Point 1:
File name:
Partition offset: 0 Seqno: 0 Offset: 0
Control Point 2:
File name:
Partition offset: 0 Seqno: 0 Offset: 0
Current File:
File name:
Partition offset: 0 Seqno: 0 Offset: 0
*END*

Analyzing database pages ...



SEQUENCE (129)
Primary pointer page: 137, Index root page: 138
Average record length: 35.00, total records: 6
Average version length: 0.00, total versions: 0, max versions: 0
Data pages: 1, data page slots: 1, average fill: 4%
Fill distribution:
0 - 19% = 1
20 - 39% = 0
40 - 59% = 0
60 - 79% = 0
80 - 99% = 0

Index RDB$PRIMARY2 (0)
Depth: 1, leaf buckets: 1, nodes: 6
Average data length: 1.00, total dup: 0, max dup: 0
Fill distribution:
0 - 19% = 1
20 - 39% = 0
40 - 59% = 0
60 - 79% = 0
80 - 99% = 0


VIDEO (131)
Primary pointer page: 142, Index root page: 143
Average record length: 0.00, total records: 1 <======= !!!!!!!
Average version length: 52.00, total versions: 1, max versions: 1
Data pages: 1, data page slots: 1634, average fill: 64%
Fill distribution:
0 - 19% = 0
20 - 39% = 0
40 - 59% = 0
60 - 79% = 1
80 - 99% = 0

Index RDB$FOREIGN4 (1)
Depth: 2, leaf buckets: 1, nodes: 1
Average data length: 2.00, total dup: 0, max dup: 0
Fill distribution:
0 - 19% = 1
20 - 39% = 0
40 - 59% = 0
60 - 79% = 0
80 - 99% = 0

Index RDB$PRIMARY3 (0)
Depth: 2, leaf buckets: 1, nodes: 1
Average data length: 3.00, total dup: 0, max dup: 0
Fill distribution:
0 - 19% = 1
20 - 39% = 0
40 - 59% = 0
60 - 79% = 0
80 - 99% = 0

========= G S T A T ============================================