Overview
TRANSACTION_TABLE_SIZE is an Altibase server property and means the maximum number of transactions that can be executed simultaneously while operating the database.
There is always one transaction in one session. Therefore, if the number of concurrent connection sessions increases, the number of concurrent transactions may increase. Therefore, when increasing the MAX_CLIENT property value, consider changing the TRANSACTION_TABLE_SIZE.
TRANSACTION_TABLE_SIZE also refers to the unique number (TID) of the transaction. This property requires caution when changing because different transactions can be recognized as one transaction if the TID causes problems due to an incorrect change.
Also, the change method differs depending on the ALTIBASE HDB version, so the related contents are summarized.
Restriction
- Depending on the ALTIBASE HDB version, there are versions that require data migration to change TRANSACTION_TABLE_SIZE. Please refer to the 'How to change' section below.
- It can only be changed to a 2^n value greater than the current value.
- It can be changed in the order of 2^n 16 -> 32 -> 64 -> 128 -> 256 -> 512 -> 1024 -> 2048 -> 4096 -> 8192 -> 16384.
- It cannot be changed from a large value to a small value.
- The number of concurrent transactions must be set higher than MAX_CLIENT because it includes all user transactions, replication transactions, and internal transactions.
- In a replication environment, it may be necessary to set up to twice of MAX_CLIENT in consideration of replication transactions.
In a replication environment, the TRANSACTION_TABLE_SIZE must all be the same between the replication target servers. If the TRANSACTION_TABLE_SIZE is different, the replication sender thread will not start.
Example
How to change
Change (offline)
From the version specified below, it can be changed to offline. (Except for ALTIBASE HDB 4 version)
ALTIBASE HDB server version | 4.3.9 | From 5.1.5.93 | From 5.3.3.48 | From 5.3.5.17 | From 5.5.1.1.0 |
|---|---|---|---|---|---|
Change (offline) | Cannot be changed. | Changeable 데이터 마이그레이션 필요. | Changeable | Changeable | Changeable |
ALTIBASE HDB server version | 4.3.9 | 5.1.5.0 ~ 5.1.5.92 | 5.3.3.0 ~ 5.3.3.47 | 5.3.5.0 ~ 5.3.5.16 | 5.5.1.0.0 ~ 5.5.1.0.9 |
|---|---|---|---|---|---|
Change (offline) | Cannot be changed. | Cannot be changed. | Cannot be changed. | Cannot be changed. | Cannot be changed. |
Change (ALTER SYSTEM)
Alter success when changing to ALTER SYSTEM may appear to be changeable by falling off, but TRANSACTION_TABLE_SIZE cannot be changed while online.
ALTIBASE HDB server version | 4.3.9 | 5.1.5 | From 5.3.3.64 | From 5.3.5.26 | From 5.5.1.2.13 |
|---|---|---|---|---|---|
Change (online) | It looks like it can be done with an alter system, but it cannot be changed. | It looks like it can be done with an alter system, but it cannot be changed. | Cannot be changed | Cannot be changed | Cannot be changed |
ALTIBASE HDB server version | 4.3.9 | 5.1.5 | 5.3.3.0 ~ 5.3.3.63 | 5.3.5.0 ~ 5.3.5.25 | 5.5.1.0.0 ~ 5.5.1.2.12 |
|---|---|---|---|---|---|
Change (online) (alter system) | It looks like it can be done with an alter system, but it cannot be changed. | It looks like it can be done with an alter system, but it cannot be changed. | It looks like it can be done with an alter system, but it cannot be changed. | It looks like it can be done with an alter system, but it cannot be changed. | It looks like it can be done with an alter system, but it cannot be changed. |
In the version where BUG-33467 is reflected, [ERR-0104E: The property [TRANSACTION_TABLE_SIZE] is read-only.] error occurs when changing to ALTER SYSTEM.
Related bug
BUG-33467 Change TRANSACTION_TABLE_SIZE property attribute to read-only. Modify so that it cannot be changed with ALTER SYSTEM.
BUG-31862 Improves the ability to change TRANSACTION_TABLE_SIZE without migration. It can only be changed to a value of 2^n greater than the current value.
Change procedures
When data migration is required
- Secure service downtime
- Database backup using aexport, iloader
- Shutdown Altibase server
- Change TRANSACTION_TABLE_SIZE in altibase.properties
- Recreate database
- Upload data to the backup backed up in 2
- Startup Altibase server
When it is possible to change to offline
- Securing service downtime
- Altibase server shutdown
- Change TRANSACTION_TABLE_SIZE in altibase.properties
- Startup Altibase server
Maximum value
Depending on the ALTIBASE HDB server version, the maximum value for TRANSACTION_TABLE_SIZE is different. In previous versions, some manuals have errors in the description of the maximum value, so please refer to the table below.
ALTIBASE HDB server version | From 4.3.9.222 | From 5.1.5.112 | From 5.3.3.91 | From 5.3.5.35 | From 5.5.1.5.3 |
|---|---|---|---|---|---|
Maximum value | 16384 | 16384 | 16384 | 16384 | 16384 |
ALTIBASE HDB server version | 4.3.9.0 ~ 4.3.9.221 | 5.1.5.0 ~ 5.1.5.111 | 5.3.3.0 ~ 5.3.3.90 | 5.3.5.0 ~ 5.3.5.34 | 5.5.1.0.0 ~ 5.5.1.5.2 |
|---|---|---|---|---|---|
Maximum value | 8192 | 8192 | 8192 | 8192 | 8192 |
Related bug
BUG-37851 The maximum value of the TRANSACTION_TABLE_SIZE value needs to be modified.
TRANSACTION_TABLE and Memory usage
When running the ALTIBASE HDB server, memory for TRANSACTION_TABLE_SIZE is allocated in advance. So, depending on the TRANSACTION_TABLE_SIZE setting, memory usage may increase slightly.
The following is an example of comparing memory usage according to the TRANSACTION_TABLE_SIZE setting value.
Memory usage may vary depending on the system environment. Please note only the difference according to the TRANSACTION_TABLE_SIZE setting value. The unit is KB.
| 1024 | 2048 | 4096 | 8192 | 16384 |
|---|---|---|---|---|---|
VSZ | 1,484,952 | 1,647,264 | 2,019,544 | 2,911,096 | 5,309,148 |
RSS | 660,900 | 825,956 | 1,164,640 | 2,093,068 | 4,465,108 |
The test server environment is as follows:
- Linux
- Environment variable MALLOC_ARENA_MAX=4
- ALTIBASE HDB 6.3.1.2.7
When TRANSACTION_TABLE_SIZE is exceeded
If the number of concurrent transactions exceeds TRANSACTION_TABLE_SIZE, the database may appear to hang due to the following phenomena.
- Unable to connect to a new session
- No response when executing SQL in the connected session
The following message appears in altibase_boot.log.
Performance View
The TRANSACTION_TABLE_SIZE setting value and the number of running transactions can be checked in V$TRANSACTION_MGR.
Error Messages
ERR-10166(errno=2) TRANSACTION_TABLE_SIZE ['4094'] is not a power of two.
This is an error message that occurs when the value of the TRANSACTION_TABLE_SIZE property is not 2^n.
2^n values are 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384.
ERR-10018(errno=0) The version of data file for backup is not compatible with the version of storage manager. Backup DB => [ Version ID = 4.11.1, Bit = 64, Endian = BIG LogSize = 10485760 Transaction Table Size = 1024 ] Server=>[ Version ID = 4.11.1, Bit = 64, Endian = BIG LogSize = 10485760 Transaction Table Size = 2048 ]
This is an error message that occurs in the version where the TRANSACTION_TABLE_SIZE set when creating the database cannot be changed.
This can happen when changing from a large value to a small value.