falcon

Enables the Falcon storage engine.

skip-falcon

Disables the Falcon storage engine.

falcon_checkpoint_schedule

The checkpoint schedule (the frequency with which fsync() is called to synchronize the in-memory and disk data). Specification is in the form of a crontab-style series of values, separated by spaces. Each specification has six fields, identical to crontab, but with the addition of seconds. Within the specification, from left to right these are:

The values specified can either be absolute, or you can specify a range or comma-separated list of matching values. For example, the specification:

7,37 * * * * *

Would checkpoint every 7 and 37 seconds of every minute, of every hour of ever day. The following specification would checkpoint only during 6am and 6pm each day at 0 and 30 seconds of every minute.

0,30 * 6-17 * * *

The default setting is every minute, seven seconds past the minute:

7 * * * * *

falcon_checksums

Enable Falcon checksum validation

falcon_consistent_read

Sets the repeatable read transaction isolation level. Set to On, repeatable read transactions are truly consistent-read. Changes made by younger transactions will not be exposed and newer records cannot be read or written within a repeatable read transaction. Set to Off, Falcon works in read-committed transaction isolation level.

The falcon_consistent_read variable has only local scope. You can set the global value, using SET GLOBAL, but this affects only the current local scope and all new connections made after the global variable was set.

falcon_debug_mask

Sets the log information that is output to the standard output of mysqld in the event of an error. The value is a bit mask; you must combine values to enables different combinations of error message types. Formerly known as falcon_log_mask. The supported values are:

Sets the log information that is output to the standard output of mysqld in the event of an error. The value is a bit mask; you must combine values to enables different combinations of error message types. Formerly known as falcon_log_mask. The supported values are:

falcon_debug_server

Specifies whether the debug server should be enabled.

falcon_disable_fsync

If true, the periodic fsync operation to synchronize data on disk is disabled. Setting this value to true may lead to data loss, but may increase performance.

Default value is false (fsync is enabled).

falcon_gopher_threads

Number of threads that process committed changes in the serial log to the database.

falcon_index_chill_threshold

The size of the pending index data that should be stored during a large transaction before the index changes are flushed to the serial log. If the index is unique, or the transaction regularly re-reads the index data, then the index data is stored in memory (for faster access). The flushing of the index data to the serial log is called chilling. Chilling pending indexes helps Falcon to load large data sets in a single transaction without exhausting memory.

For versions up to MySQL 6.0.6, the value is specified in megabytes, with the minimum accepted value is 1, the maximum is 1024 and the default value is 4.

For versions of MySQL 6.0.7 and later, the value is specified in bytes, with the minimum accepted value is 1048576, the maximum is 1073741824 and the default value is 4194304.

This configuration option is available within mysqld as a server variable.

falcon_initial_allocation

The amount of space, in MB, that should be preallocated on disk when a new Falcon tablespace file is created.

This configuration option was removed in MySQL 6.0.6.

falcon_io_threads

The number of asynchronous threads to be used when performing writes to disk.

falcon_max_transaction_backlog

The maximum number of pending transactions that will be active before the update process is blocked until the number of pending transactions reduces.

This configuration option was removed in MySQL 6.0.6.

falcon_large_blob_threshold

BLOB data below this threshold is stored in data pages, instead of BLOB pages. This can improve performance for smaller blobs because only the serial log needs to be flushed at the end of a transaction, and not the serial log and the blob pages.

falcon_lock_wait_timeout

The period (in seconds) that a Falcon transaction will wait for another transaction to complete when both transactions need access to a locked table. A value 0 indicates that Falcon will wait indefinitely for another transaction to complete.

This variable was added in MySQL 6.0.4. (Previously, in 6.0.3, there was a variable named falcon_lock_timeout which was measured in milliseconds and had a default of 0.)

falcon_page_cache_size

Sets the amount of memory that will be allocated for caching pages from the tablespace file.

falcon_page_size

Controls the size of the pages used to store information within the tablespace. Valid sizes are 2, 4, 8, 16 and 32 KB.

The specified page size also affects the maximum index key lengths supported. The table below shows the relationship between the page size and the maximum index key length.

falcon_record_chill_threshold

The number of Mbytes of pending record data that Falcon will keep in memory during a large transaction before flushing these records to the serial log. This flushing is called chilling since it makes the data not immediately available. If chilled records are accessed again during the transaction, they are immediately restored (thawed) from the serial log. Chilling pending records helps Falcon to accomplish very large transactions without running out of memory.

For versions up to MySQL 6.0.6, the value is specified in megabytes, with the minimum accepted value is 1, the maximum is 1024 and the default value is 5.

For versions of MySQL 6.0.7 and later, the value is specified in bytes, with the minimum accepted value is 1048576, the maximum is 1073741824 and the default value is 5242880.

falcon_record_memory_max

Sets the maximum amount of memory that will be allocated for caching record data.

falcon_record_scavenge_floor

The percentage of falcon_record_scavenge_threshold that will be retained in the record cache after the scavenger thread has completed execution.

You can determine the minimum size of the record cache using this formula:

min(falcon_record_memory_max
    * (falcon_record_scavenge_threshold/100)
    * (falcon_record_scavenge_floor/100))

falcon_record_scavenge_threshold

The percentage of falcon_record_memory_max that will cause the scavenger thread to start removing old generations of records from the record cache.

Default value is 67. The minimum accepted value is 10, and the maximum is 100.

falcon_scavenge_schedule

The record scavenging schedule, specified as a crontab style schedule. See falcon_checkpoint_schedule.

falcon_serial_log_buffers

The number of memory windows allocated for the Falcon serial log. Each window is 1 MByte in size. Formerly falcon_log_windows.

falcon_serial_log_dir

Sets the directory for storing the serial log. The file names used by the serial log (two files are create for storing serial data) are allocated according to the name of the tablespace.

falcon_serial_log_priority

Sets whether the serial log has priority other writes.

falcon_support_xa

Specifies whether Falcon should support two-phase commit. When set to 0 (default), commits are single phase. When set to 1, Falcon reports itself as a two-phase commit supporting engine and supports two-phase commits.

falcon_use_deferred_index_hash

Enable the deferred index hash.

Default is off

falcon_use_sectorcache

Use the sector cache. When enabled, disk reads are in blocks of 64KB. When switched off, disk reads are based on the page size (as set by falcon_page_size.

Default is off

falcon_use_supernodes

Use supernodes within the Falcon index. Supernodes are an array of 16 vectors into each index page to keys that are fully expanded with noprefix compression. This allows the page to be searched quicker using a binary search of supernode keys followed by the normal sequential search. Without enabling supernodes, the whole page has to be searched sequentially.

Default is on

--falcon-max-record-memory=#

--falcon-min-record-memory=#

--falcon-page-cache-size=#

--falcon enables the Falcon storage engine.

--skip-falcon disables the Falcon Storage Engine.