diagnostics. This was written in order to better track down
Issue #313 in InnoDB Hot Backup.
MLOG_LSN: A new redo log entry type, for recording the current log
sequence number (LSN). This will be checked in an assertion in
recv_parse_log_rec().
rb://161, discussed with Sunny and Vasil.
This patch introduces heuristics based flushing rate of dirty pages to
avoid IO bursts at checkpoint.
1) log_capacity / log_generated per second gives us number of seconds
in which ALL dirty pages need to be flushed. Based on this rough
assumption we can say that
n_dirty_pages / (log_capacity / log_generation_rate) = desired_flush_rate
2) We use weighted averages (hard coded to 20 seconds) of
log_generation_rate to avoid resonance.
3) From the desired_flush_rate we subtract the number of pages that have
been flushed due to LRU flushing. That gives us pages that we should
flush as part of flush_list cleanup. And that is the number (capped by
maximum io_capacity) that we try to flush from the master thread.
Knobs:
======
innodb_adaptive_flushing: boolean, global, dynamic, default TRUE.
Since this heuristic is very experimental and has the potential to
dramatically change the IO pattern I think it is a good idea to leave a
knob to turn it off.
Approved by: Heikki
/*********************************
comments to Doxygen /** style like this:
/*****************************//**
This conversion was performed by the following command:
perl -i -e 'while(<ARGV>){if (m|^/\*{30}\**$|) {
s|\*{4}$|//**| if ++$com>1; $_ .= "\@file $ARGV\n" if $com==2}
print; if(eof){$.=0;undef $com}}' */*[ch] include/univ.i
This patch was created by running the following commands:
for i in */*[ch]; do doxygenify.pl $i; done
perl -i -pe 's#\*{3} \*/$#****/#' */*[ch]
where doxygenify.pl is
https://svn.innodb.com/svn/misc/trunk/tools/doxygenify.pl r510
Verified the consistency as follows:
(0) not too many /* in: */ or /* out: */ comments left in the code:
grep -l '/\*\s*\(in\|out\)[,:/]' */*[ch]
(1) no difference when ignoring blank lines, after stripping all
C90-style /* comments */, including multi-line ones, before and after
applying this patch:
perl -i -e 'undef $/;while(<ARGV>){s#/\*(.*?)\*/##gs;print}' */*[ch]
diff -I'^\s*$' --exclude .svn -ru TREE1 TREE2
(2) after stripping @return comments and !<, generated a diff and omitted
the hunks where /* out: */ function return comments were removed:
perl -i -e'undef $/;while(<ARGV>){s#!<##g;s#\n\@return\t.*?\*/# \*/#gs;print}'\
*/*[ch]
svn diff|
perl -e 'undef $/;$_=<>;s#\n-\s*/\* out[:,]([^\n]*?)(\n-[^\n]*?)*\*/##gs;print'
Some unintended changes were left. These will be removed in a
subsequent patch.
* Remove old Innobase copyright lines from C source files
* Add a reference to the GPLv2 license as recommended by the lawyers
at Oracle Legal
[Step 10/28]
symbols. Use it for all definitions of non-static variables and functions.
lexyy.c, make_flex.sh: Declare yylex as UNIV_INTERN, not static. It is
referenced from pars0grm.c.
Actually, according to
nm .libs/ha_innodb.so|grep -w '[ABCE-TVXYZ]'
the following symbols are still global:
* The vtable for class ha_innodb
* pars0grm.c: The function yyparse() and the variables yychar, yylval, yynerrs
The required changes to the Bison-generated file pars0grm.c will be addressed
in a separate commit, which will add a script similar to make_flex.sh.
The class ha_innodb is renamed from class ha_innobase by a #define. Thus,
there will be no clash with the builtin InnoDB. However, there will be some
overhead for invoking virtual methods of class ha_innodb. Ideas for making
the vtable hidden are welcome. -fvisibility=hidden is not available in GCC 3.
log_block_calc_checksum(), log_block_get_checksum(): Add const qualifiers.
log_block_calc_checksum(): Split a long expression to more readable chunks.
Some compilers might optimize this better.
