Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

system-variables: update permitted ranges (#6665) #6700

Closed
wants to merge 1 commit into from
Closed

system-variables: update permitted ranges (#6665) #6700

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
60 changes: 60 additions & 0 deletions system-variables.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -553,7 +553,12 @@ Constraint checking is always performed in place for pessimistic transactions (d

- Scope: GLOBAL
- Default value: `4`
<<<<<<< HEAD
- Range: `[1, 128]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of the DDL operation in the `re-organize` phase.

### tidb_disable_txn_auto_retry
Expand All @@ -574,7 +579,12 @@ Constraint checking is always performed in place for pessimistic transactions (d

- Scope: SESSION | GLOBAL
- Default value: `15`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of the `scan` operation.
- Use a bigger value in OLAP scenarios, and a smaller value in OLTP scenarios.
- For OLAP scenarios, the maximum value cannot exceed the number of CPU cores of all the TiKV nodes.
Expand Down Expand Up @@ -840,7 +850,12 @@ MPP is a distributed computing framework provided by the TiFlash engine, which a

- Scope: SESSION | GLOBAL
- Default value: `5`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))

This variable is used to set the concurrency of the following SQL operators (to one value):

Expand Down Expand Up @@ -885,7 +900,12 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified

- Scope: GLOBAL
- Default value: `-1`
<<<<<<< HEAD
- Range: `[1, 128]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- Specifies the number of threads in the [Resolve Locks](/garbage-collection-overview.md#resolve-locks) step of GC. A value of `-1` means that TiDB will automatically decide the number of garbage collection threads to use.

### tidb_gc_enable <span class="version-mark">New in v5.0</span>
Expand Down Expand Up @@ -952,7 +972,12 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified

- Scope: SESSION | GLOBAL
- Default value: `-1`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of the `hash join` algorithm.
- A value of `-1` means that the value of `tidb_executor_concurrency` will be used instead.

Expand All @@ -964,7 +989,12 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified

- Scope: SESSION | GLOBAL
- Default value: `-1`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of executing the concurrent `hash aggregation` algorithm in the `final` phase.
- When the parameter of the aggregate function is not distinct, `HashAgg` is run concurrently and respectively in two phases - the `partial` phase and the `final` phase.
- A value of `-1` means that the value of `tidb_executor_concurrency` will be used instead.
Expand All @@ -977,7 +1007,12 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified

- Scope: SESSION | GLOBAL
- Default value: `-1`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of executing the concurrent `hash aggregation` algorithm in the `partial` phase.
- When the parameter of the aggregate function is not distinct, `HashAgg` is run concurrently and respectively in two phases - the `partial` phase and the `final` phase.
- A value of `-1` means that the value of `tidb_executor_concurrency` will be used instead.
Expand All @@ -998,7 +1033,12 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified

- Scope: SESSION | GLOBAL
- Default value: `-1`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of the `index lookup` operation.
- Use a bigger value in OLAP scenarios, and a smaller value in OLTP scenarios.
- A value of `-1` means that the value of `tidb_executor_concurrency` will be used instead.
Expand All @@ -1011,7 +1051,12 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified

- Scope: SESSION | GLOBAL
- Default value: `-1`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of the `index lookup join` algorithm.
- A value of `-1` means that the value of `tidb_executor_concurrency` will be used instead.

Expand All @@ -1027,7 +1072,12 @@ For a system upgraded to v5.0 from an earlier version, if you have not modified

- Scope: SESSION | GLOBAL
- Default value: `1`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of the `serial scan` operation.
- Use a bigger value in OLAP scenarios, and a smaller value in OLTP scenarios.

Expand Down Expand Up @@ -1287,7 +1337,12 @@ explain select * from t where age=5;

- Scope: SESSION | GLOBAL
- Default value: `-1`
<<<<<<< HEAD
- Range: `[-1, 2147483647]`
=======
- Range: `[-1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency of the `Projection` operator.
- A value of `-1` means that the value of `tidb_executor_concurrency` will be used instead.

Expand Down Expand Up @@ -1487,7 +1542,12 @@ SET tidb_slow_log_threshold = 200;

- Scope: SESSION | GLOBAL
- Default value: `-1`
<<<<<<< HEAD
- Range: `[1, 2147483647]`
=======
- Range: `[1, 256]`
- Unit: Threads
>>>>>>> 966c86dfe (system-variables: update permitted ranges (#6665))
- This variable is used to set the concurrency degree of the window operator.
- A value of `-1` means that the value of `tidb_executor_concurrency` will be used instead.

Expand Down