The combined effort of all workers of updating EMAverage is needed for precision,
statistics and making parts of it adaptive (rather than hardcoded or configured).
Fix comments.
Fix a bug in make_valid().
Change sync time (when the average should be pushed to the server EMA)
to only depend on time, not use sample_max. This decreases the amount of
sync calls, and allows for a much shorter sync time. Testing shows this to be
more stabel and allows to make sample_max adaptive .
Fix comments.
Fix a bug in make_valid().
Change sync time (when the average should be pushed to the server EMA)
to only depend on time, not use sample_max. This decreases the amount of
sync calls, and allows for a much shorter sync time. Testing shows this to be
more stabel and allow better control of the sample_max.
As buffers are meant to be used only within a particular session, the
atomic operations are no longer necessary and can thus be removed. This
removes the extra overhead that the atomic operations add.
The reads now read as much of the data as is available to reduce the
number of distinct malloc calls that need to be made. The SSL_read also
now allocates the buffer before reading into it so that the amount of
copying is reduced.
Also removed some of the not quite helpful debug messages.
If the log file is successfully opened, both stdout and stderr are
redirected to it. This helps catch ASAN reports without having to read the
system journal files.
As the output is redirected to a file, some of the output was made visible
only in non-daemon mode. This helps keep the log file clean and readable.
The client connections had the Nagle algorithm enabled which could cause
bad performance with smaller workloads. The common network configuration
code in utils.cc, currently used by the backend connections, sets it
properly.
Replaced SPINLOCK with std::mutex where possible, leaving out the more
complex cases. The big offenders remaining are the binlogrouter and the
gateway.cc OpenSSL locks.
In progress, does not yet overwrite existing code.
The new promotion mechanism automatically retries queries which timed out. It also
handles multimaster situations correctly.
Added `match` and `exclude` functionality. This allows versatile filtering
without a large investment of development time by leveraging the benefits
of PCRE2 regular expressions.
Also cleaned up the filter and removed the single table matching and
active parameter that were obsoleted by the regular expression parameters.
The additions into the server.h header used C++ language which caused C
programs to fail to compile. Moved the implementation of the EMAverage
class into the private Server class in the server.hh header and exposed it
via functions in the server.h header. Also temporarily moved
almost_equal_server_scores into the public server.hh as there is no
service.hh header.
See script directory for method. The script to run in the top level
MaxScale directory is called maxscale-uncrustify.sh, which uses
another script, list-src, from the same directory (so you need to set
your PATH). The uncrustify version was 0.66.
The math becomes simpler when the weight is inverted, i.e. a simple multiplication
to get the (inverse) score. Inverse weights are normalized to the range [0..1] where a lower
number is a higher weight,
The enum select_criteria_t is used to provide a std::function that takes the backends
as vector (rather than the prior pairwise compares) and returns the best backend.