#include <log0log.h>
Detailed Description
Redo log buffer
Definition at line 737 of file log0log.h.
Member Data Documentation
first free offset within the log buffer
Definition at line 742 of file log0log.h.
| ulint log_t::buf_next_to_write |
The fields involved in the log buffer flush first offset in the log buffer where the byte content may not exist written to file, e.g., the start offset of a log record catenated later; this is advanced when a flush operation is completed to all the log groups
Definition at line 785 of file log0log.h.
log buffer size in bytes
Definition at line 758 of file log0log.h.
| ibool log_t::check_flush_or_checkpoint |
this is set to TRUE when there may be need to flush the log buffer, or preflush buffer pool pages, or make a checkpoint; this MUST be TRUE when lsn - last_checkpoint_lsn > max_checkpoint_age; this flag is peeked at by log_free_check(), which does not reserve the log mutex
Definition at line 771 of file log0log.h.
| byte* log_t::checkpoint_buf |
checkpoint header is read to this buffer
Definition at line 901 of file log0log.h.
this latch is x-locked when a checkpoint write is running; a thread should wait for this without owning the log mutex
Definition at line 895 of file log0log.h.
| lsn_t log_t::current_flush_lsn |
end lsn for the current running write + flush operation
Definition at line 821 of file log0log.h.
| lsn_t log_t::flushed_to_disk_lsn |
how far we have written the log AND flushed to disk
Definition at line 824 of file log0log.h.
| lsn_t log_t::last_checkpoint_lsn |
latest checkpoint lsn
Definition at line 889 of file log0log.h.
| time_t log_t::last_printout_time |
when log_print was last time called
Definition at line 855 of file log0log.h.
mutex to serialize access to the flush list when we are putting dirty blocks in the list. The idea behind this mutex is to be able to release log_sys->mutex during mtr_commit and still ensure that insertions in the flush_list happen in the LSN order.
Definition at line 747 of file log0log.h.
| lsn_t log_t::log_group_capacity |
Fields involved in checkpoints capacity of the log group; if the checkpoint age exceeds this, it is a serious error because it is possible we will then overwrite log and spoil crash recovery
Definition at line 860 of file log0log.h.
log sequence number
Definition at line 741 of file log0log.h.
| ulint log_t::max_buf_free |
recommended maximum value of buf_free, after which the buffer is flushed
Definition at line 759 of file log0log.h.
| lsn_t log_t::max_checkpoint_age |
this is the maximum allowed value for lsn - last_checkpoint_lsn when a new query step is started
Definition at line 883 of file log0log.h.
| lsn_t log_t::max_checkpoint_age_async |
when this checkpoint age is exceeded we start an asynchronous writing of a new checkpoint
Definition at line 878 of file log0log.h.
| lsn_t log_t::max_modified_age_async |
| lsn_t log_t::max_modified_age_sync |
mutex protecting the log
Definition at line 745 of file log0log.h.
number of log i/os initiated thus far
Definition at line 851 of file log0log.h.
| ulint log_t::n_log_ios_old |
number of log i/o's at the previous printout
Definition at line 853 of file log0log.h.
| ulint log_t::n_pending_checkpoint_writes |
number of currently pending checkpoint writes
Definition at line 893 of file log0log.h.
| ulint log_t::n_pending_writes |
number of currently pending flushes or writes
Definition at line 826 of file log0log.h.
| lsn_t log_t::next_checkpoint_lsn |
next checkpoint lsn
Definition at line 891 of file log0log.h.
| ib_uint64_t log_t::next_checkpoint_no |
next checkpoint number
Definition at line 887 of file log0log.h.
this event is in the reset state when a flush or a write is running; a thread should wait for this without owning the log mutex, but NOTE that to set or reset this event, the thread MUST own the log mutex!
Definition at line 832 of file log0log.h.
during a flush, this is first FALSE and becomes TRUE when one log group has been written or flushed
Definition at line 838 of file log0log.h.
this event is reset when the flush or write has not yet completed for any log group; e.g., this means that a transaction has been committed when this is set; a thread should wait for this without owning the log mutex, but NOTE that to set or reset this event, the thread MUST own the log mutex!
Definition at line 842 of file log0log.h.
padding to prevent other memory update hotspots from residing on the same memory cache line
Definition at line 738 of file log0log.h.
| ulint log_t::write_end_offset |
the data in buffer has been written up to this offset when the current write ends: this field will then be copied to buf_next_to_write
Definition at line 816 of file log0log.h.
end lsn for the current running write
Definition at line 814 of file log0log.h.
| lsn_t log_t::written_to_all_lsn |
first log sequence number not yet written to some log group; for this to be advanced, it is enough that the write i/o has been completed for all log groups. Note that since InnoDB currently has only one log group therefore this value is redundant. Also it is possible that this value falls behind the flushed_to_disk_lsn transiently. It is appropriate to use either flushed_to_disk_lsn or write_lsn which are always up-to-date and accurate.
Definition at line 799 of file log0log.h.
| lsn_t log_t::written_to_some_lsn |
first log sequence number not yet written to any log group; for this to be advanced, it is enough that the write i/o has been completed for any one log group
Definition at line 793 of file log0log.h.
The documentation for this struct was generated from the following file:
1.8.1.2 
