gbak: Incorrect total statistics for restore

[Noremos]

I restored a 74M database (~9401 pages), but the number of writes in the gbak output shows only 3087.

gbak -c -user SYSDBA ./mydb.fbk ./mydb.fdb -v -ST W
gbak: writes
gbak:      0 opened file ./mydb.fbk
gbak:      0 transportable backup -- data in XDR format
gbak:      0            backup file is compressed
gbak:      0 backup version is 11
gbak:    781 created database ./mydb.fdb, page_size 8192 bytes
gbak:      2 started transaction
gbak:      0 restoring domain RDB$1
gbak:      0 restoring domain RDB$2
...
gbak:     11 finishing, closing, and going home
gbak:   3087 total statistics
gbak:adjusting the ONLINE and FORCED WRITES flags

ll ./mydb.fdb
-rw-rw---- 1 art art 77012992 янв 15 12:59 ./mydb.fdb

77012992 / 8192 = 9401
9401 > 3087

The CCH logging clearly shows almost 10,000 writes

[pavel-zotov]

I can't reproduce original problem.
Consider following script (it is from another ticket, but i hope this no matters):

set bail on;
set list on;
set echo on;
shell if exist c:\temp\tmp4test.fdb del c:\temp\tmp4test.fdb;
create database 'c:\temp\tmp4test.fdb' user 'sysdba' password 'masterkey' page_size 8192;
commit;
show version;
recreate sequence g;
recreate table test(id int, b blob);
set autoterm on;
execute block as
    declare n int;
begin
    insert into test(id, b) values(gen_id(g,1), gen_uuid());
    insert into test(id, b)
    values(
            gen_id(g,1)
            ,(select list(gen_uuid()) as s from rdb$types,rdb$types)
          );
 
    insert into test(id, b)
    values(
            gen_id(g,1)
            ,(select list(gen_uuid()) as s from (select 1 x from rdb$types,rdb$types,rdb$types rows 800000))
          );
end
;
commit;

Now let's do b/r using FB 6.0.0.594 (ServerMode = Super):

gbak -b -g c:\temp\tmp4test.fdb stdout | C:\FB\60SS\gbak -rep -v -st w stdin c:\temp\tmptest.restored.fdb 1>gh-8394.tmp.restore.6.0.0.594.log 2>&1

Log is:

gbak: writes
gbak:      0 transportable backup -- data in XDR format
gbak:      0         backup file is compressed
gbak:      0 backup version is 11
gbak:    781 created database c:\temp\tmptest.restored.fdb, page_size 8192 bytes
gbak:      2 started transaction
gbak:      0 restoring domain RDB$1
...
gbak:      9 finishing, closing, and going home
gbak:   3185 total statistics
gbak:adjusting the ONLINE and FORCED WRITES flags

Size of restored .fdb: 21610496
21610496 / 8192 = 2638.0 -- and this is less than in log of "gbak -st w"

PS. Used firebird.conf:

AuthServer = Srp, Win_Sspi, Legacy_Auth
BugCheckAbort = 1
ClearGTTAtRetaining = 0
ClientBatchBuffer = 131072
ConnectionIdleTimeout = 0
DefaultDBCachePages = 10K
ExtConnPoolLifeTime = 10
ExtConnPoolSize = 10
ExternalFileAccess = Full
InlineSortThreshold = 1000
IpcName = xnet_fb6x_ss
KeyHolderPlugin = fbSampleKeyHolder
MaxIdentifierByteLength = 252
MaxIdentifierCharLength = 63
MaxParallelWorkers = 8
MaxUnflushedWrites = -1
MaxUnflushedWriteTime = -1
ParallelWorkers = 2
ReadConsistency = 0
RemoteServicePort = 3600
ServerMode = Super
SnapshotsMemSize = 64K
StatementTimeout = 600
TempCacheLimit = 1G
TipCacheBlockSize = 4M
UseFileSystemCache = true
UserManager = Srp, Legacy_UserManager
WireCrypt = Enabled
WireCryptPlugin = ChaCha, Arc4

[Noremos]

The issue has already been fixed. The latest affected version is 6.0.0.588.

[pavel-zotov]

But in 6.0.0.584 (15-jan-2025) above mentioned script gives similar result:

gbak: writes 
gbak:      0 transportable backup -- data in XDR format
gbak:      0 		backup file is compressed
gbak:      0 backup version is 11
gbak:    781 created database c:\temp\tmptest.restored.fdb, page_size 8192 bytes
...
gbak:      9 finishing, closing, and going home
gbak:   3165 total statistics
gbak:adjusting the ONLINE and FORCED WRITES flags

(vs "gbak: 3185 total statistics" in 6.0.0.594)

So: how to reproduce source problem (i.e. when restore log contains total statistics less than num of pages in FDB file) ?

[Noremos]

I reproduced it on the EMPLOYEE databse with default configs. Here is the backup: https://drive.google.com/file/d/1fHg0Br1F7ZZc56ryHDoHpKQd-eppQPfV/view?usp=sharing

[Noremos]

My bad, not EMPLOYEE. It is a TPCH database

[pavel-zotov]

It seems that value of DefaultDBCachePages can affect on outcome.
I have DefaultDBCachePages = 10K and this is greated than 77012992 / 8192 = 9401
When FB is running with such value of DefaultDBCachePages, i get in restore log "gbak: 9955 total statistics"
When DefaultDBCachePages = 5K then "gbak: 5625 total statistics", etc.