Question
What is the FME_TEMP environment variable?
Answer
FME_TEMP
FME puts many temporary files in the system temporary directory, which on some Windows versions defaults to C:\temp or under the user local temp directory (i.e.C:\Users\mark\AppData\Local\Temp).If there is not enough room in this directory due to space limitations on the C drive, you can override this default and send the FME temporary files to a different directory using the FME_TEMP environment variable.(InWindows 2000的和W7, look under Control Panel | System | Advanced | Environment Variables.In的Windows 8和Windows 10look under Control Panel | System and Security | System | Advanced system settings | Environment Variables).
FME searches for a temp directory using the following tests in order:
- 如果用户环境变量FME_TEMP存在，利用其作为临时目录路径值。
- 如果用户环境变量TEMP存在，使用它作为临时目录路径值。
- 如果FME正在运行的驱动器上存在一个名为\ temp目录，使用该目录。
- 如果驱动器上存在一个名为\ tmp目录上FME正在运行时，使用该目录。
If all of these tests fail to locate an existing temporary directory, FME ends with an error message indicating that it couldn't open a temporary file.
To remedy this situation, either:
Create an
要么
定义FME_TEMP或TEMP用户环境变量，无论是全系统或用于在其上FME正在运行的用户帐户。例如，如果临时文件将被放置到目录j：\划伤，那么环境变量FME_TEMP将被设置到j：FME之前\从头开始运行。
某些操作系统默认为临时驱动RAM驱动器。这意味着高速缓存FME可消耗RAM这会影响性能。设置FME_TEMP将迫使FME缓存，其可以提高性能物理驱动器。
OnLINUXplatforms you'd set the environment variable using:
export FME_TEMP=/
You'd probably set that variable in your .bashrc which is run when the machine starts up
FME Workbench creates temporary mapping files in the directory pointed to by the TEMP environment variable, if set.Otherwise, C:\temp is used.
If anyone is using the SAIF format, this format behaves differently (for historical reasons).SAIF also uses temporary files as it reads/writes, but that module uses the environment variables...
- STK_TMPDIR
- TMPDIR
in the order shown to figure out what temporary directories the SAIF writer/reader will use.
FME Server will also make use of the FME_TEMP directory.Typically, the automatically generated directory for data download and data streaming results looks something like
C:\ProgramData\Safe Software\FME Server\resources\system\temp\requestdata\FME_4F366F63_1437683309563_2288
but this can be overridden using FME_TEMP.
Performance Tuning with FME_TEMP
Many of the FME temporary files are created when caching data for larger datasets or for display in FME Universal Viewer or Data Inspector.Using a faster hard drive can make quite a difference to the FME translation if disc cache I/O speeds are improved.An example would be if you have an SSD (Solid State Drive) on your computer.这些通常比传统的HHD硬盘相当快一点，所以如果你可以点你FME_TEMP到SSD，然后用更大的数据集进行操作时，你会看到一点点的性能提升。更多关于性能优化的：性能优化FME
