cmogstored

cmogstored is an open source and completely free command-line software that implements the mogstored storage component of MogileFS in C. The program is implemented only in C and it doesn't use the Perl language at runtime.

Features at a glance

Key features include a low memory footprint, multi-threaded design, support for HTTP/1.1 pipelining and persistent connections, support for partial and chunked HTTP/1.1 PUT requests, as well as checksumming support.

Additionally, the software supports partial GET requests, includes an extensive test suite, and offers a graceful shutdown via SIGQUIT. It is the only component that needs to be installed on a MogileFS storage node.

Command-line options

Various command-line options are implemented in the cmogstored program, such as the ability to set a custom configuration file, to daemonize the program, to specify the IP address and port of the web server to listen on, to set the number of simultaneous clients to serve, to specify the path to the PID file, as well as to specify the IP address and port where the sidechannel and management interfaces listen on.

Getting started with cmogstored

To install and use the cmogstored software on your GNU/Linux distribution, you will have to first download the latest version of the program from Softoware, save the archive somewhere on your local filesystem (preferrably your Home directory), and extract its contents with an archive manager utility.

After you’ve extract the archive’s contents, it is time to open a Terminal app and navigate to the location of the extracted archive files, using the ‘cd’ command (e.g. cd /home/softoware/cmogstored-1.4.1). Then, run the ‘./configure && make’ command to configure and compile the program, followed by the ‘sudo make install’ command to install it system wide and make it available to all users.

What is new in this release:

• This version fixes build problems with Debian GNU/kFreeBSD support.
• There are also build system upgrades for automake 1.14 and test case cleanups, but no changes to any of the core code.
• There are no changes nor need to upgrade if you're on anything other than Debian GNU/kFreeBSD.

What is new in version 1.3.2:

• This version speeds up graceful shutdown on FreeBSD when the system is busy.
• There are also several minor bugfixes and documentation updates.

What is new in version 1.3.1:

• This version fixes a bug in the undocumented multi-process configuration feature.
• Very few users are affected, but users of this undocumented feature must upgrade.
• This bug has existed forever, but only manifested since cmogstored 1.3.0.

What is new in version 1.3.0:

• This version contains improvements for storage hosts at the extreme ends of the performance scale.
• For large machines with many cores, memory/thread usage is reduced because there were too many acceptor threads.
• There are more improvements for smaller machines, especially those with slow/imbalanced drive speeds and few CPUs.

What is new in version 1.2.2:

• This minor maintenance release fixes build problems with compilers which default to -march=i386.
• It also fixes utilization reporting of device names with "-" in them.

What is new in version 1.2.1:

• This version only fixes an assertion failure during graceful shutdown while MogileFS fsck is running with checksums enabled.

What is new in version 1.2.0:

• This version supports nginx-style binary upgrades via SIGUSR2.
• Slow/unreliable mount points should have less effect on iostat sidechannel clients once the process is running.
• Error handling has improved in a few places when nofile/nproc limits are hit.