2.20.1.2 Linux Binary Distribution Notes

The Linux-Intel binary and RPM releases of MySQL are configured for the highest possible speed. We are always trying to use the fastest stable compiler available.

The binary release is linked with -static, which means you do not normally need to worry about which version of the system libraries you have. You need not install LinuxThreads, either. A program linked with -static is slightly larger than a dynamically linked program, but also slightly faster (3% to 5%). However, one problem with a statically linked program is that you can't use user-defined functions (UDFs). If you are going to write or use UDFs (this is something for C or C++ programmers only), you must compile MySQL yourself using dynamic linking.

A known issue with binary distributions is that on older Linux systems that use libc (such as Red Hat 4.x or Slackware), you get some (nonfatal) issues with host name resolution. If your system uses libc rather than glibc2, you probably will encounter some difficulties with host name resolution and getpwnam(). This happens because glibc (unfortunately) depends on some external libraries to implement host name resolution and getpwent(), even when compiled with -static. These problems manifest themselves in two ways:

Another solution, which solves both problems, is not to use a binary distribution. Obtain a MySQL source distribution (in RPM or .tar.gz format) and install that instead.

On some Linux 2.2 versions, you may get the error Resource temporarily unavailable when clients make a great many new connections to a mysqld server over TCP/IP. The problem is that Linux has a delay between the time that you close a TCP/IP socket and the time that the system actually frees it. There is room for only a finite number of TCP/IP slots, so you encounter the resource-unavailable error if clients attempt too many new TCP/IP connections over a short period of time. For example, you may see the error when you run the MySQL test-connect benchmark over TCP/IP.

We have inquired about this problem a few times on different Linux mailing lists but have never been able to find a suitable resolution. The only known fix is for clients to use persistent connections, or, if you are running the database server and clients on the same machine, to use Unix socket file connections rather than TCP/IP connections.