One more code issue: a bitmap file is created/opened using either os_file_create_simple() during startup , either os_file_create() during rotate. This results in selective flush_method honoring.
After discussing with Alexey the conclusion is to not to open the bitmaps as data or log files, so that they ignore flush_method, by using os_*_simple() interface only. Then issue a posix_fadvice(DONTNEED) after a block write.
One more code issue: a bitmap file is created/opened using either os_file_ create_ simple( ) during startup , either os_file_create() during rotate. This results in selective flush_method honoring.
After discussing with Alexey the conclusion is to not to open the bitmaps as data or log files, so that they ignore flush_method, by using os_*_simple() interface only. Then issue a posix_fadvice( DONTNEED) after a block write.