System Optimizer X 4.7.4, by MKD Software
Posted: 15-Jun-2006

2 1/2 out of 5 Mice

Vendor: MKD Software Type: SHAREWARE

Reviewer: Andy Wallis Class: UTILITY
$12   Download

Overview System Optimizer X 4.7.4 (SOX) is a small utility written by MKD Software to designed to speed up Mac OS X 10.2 or later machines. The GUI is a series of buttons for each category and a text output window. The output window displays some UNIX command line outputs. One has the option of prebinding executables, running the stock Mac OS X maintenance scripts, modifying TCP and RAM settings, cleaning the system cache, and modifying the underlying BSD subsystem permissions.


  • Update Prebindings - Updating executable library prebindings uses the OS X built-in update_prebinding tool to update links between executables (applications) and their needed system libraries to speed their launch time.
  • Run System Maintenance Scripts - Mac OS X has three built in system maintenance scripts, "daily", "weekly" and "monthly". These scripts do things like update and back up system databases, rotate and clean log files, and check security settings, and are scheduled by the system to run at between 3AM and 5AM accordingly. The "Maintenance" feature of SOX allows you to run these scripts manually.
  • Clean System/Application Cache - The Mac OS X system, as well as many individual applications, use a caching system to generally speed up performance. This cache can become corrupted, however, and cause "flaky" behavior, such as the "beach-ball effect." Cleaning this cache will often eliminate this, and allow applications and system processes to start fresh.
  • Repair UNIX File Permissions - UNIX uses a file permissions system to limit access to sensitive files. These permissions frequently need maintenance, however, and can cause many unpredictable problems. System Optimizer X uses the built-in DiskUtil binary to repair your startup volume's file permissions.
  • Optimization Your Internet Connection - Internet Optimization adjusts TCP buffer sizes to their optimum sizes for your type of internet connection. Advanced users can manually adjust buffer sizes and turn packet delay and RFC1323 on and off.
  • Compress Minimized Windows - This feature enables the system built-in "window buffer compression" to compress the RAM used for windows which are minimized in the dock. This will free up RAM for other application and the system. Generally, window buffer compression is not needed unless you have less than 256 megabytes of RAM. The downfall to using window buffer compression is that minimized windows take a split-second longer to pop out of the dock when they are clicked, if running on a slower machine
  • Schedule Tasks - System Optimizer X's schedule can be used to automatically run takes (update prebindings, run system maintenance scripts, clean system/application cache, and repair file permissions) at a custom time and at weekly, bi-weeky, monthly, or bi-monthly intervals.
  • Optimize - As a convenience, the "Optimize" feature queues tasks to run in succession: repair file permissions, update prebindings, run system maintenance scripts, and clean system and application cache.

The installer is the standard Mac OS X Installer. The product is installed in six clicks and does not require an admin password. The software itself can be locked so that only an admin can use it by clicking a lock icon.

In Use
The main SOX window provides a series of buttons for performing different system optimizations, such as prebind executables, modify permissions, clean the system cache and run the Mac OS X stock cron entries. It also provides tools for tweaking your internet and memory settings, as well as scheduling tasks. When the "Optimize" button is clicked, SOX performs the primary optimizations in sequence (repair permissions, update prebindings, run maintenance scripts, and clean caches).

System Optimizer X - Main Window

The results are displayed in the text area below the SOX toolbar.

Log of Activity Performed by System Optimizer X

Experienced UNIX users will see and understand the commands that SOX is actually running for each button and its output. Users who have not used the CLI before will be perplexed at the output. The cache cleaning and system maintenance panels are incompatible with FileVault. When the user runs SOX for the first time, a popup window appears warning users of this incompatibility.

System Optimizer X - Optimize Completion

Applications on a Macintosh running Mac OS X consists of the program itself and its libraries. When an application is loaded, the OS will also load the libraries that it needs into RAM. It does this by opening the library and putting it wherever there is enough free space in RAM. Mac OS X then has to let the application know where it is. In order to speed this up, Mac OS X can update a library to have it load in a predetermined location. This is called prebinding. A prebound application will simply put the library in the predetermined location and start running the application. New software installed on a machine will not have had its binding updated for the machine, so it makes sense to run a tool like System Optimizer X to update the prebindings before running the software.

Mac OS X uses a set of directories to store temporary files that an application or the OS needs to work with. This is referred to as a cache. Both the system at large and each user has a cache. As an example, a user's cache would have a temporary file for Apple Mail while the user is composing a message or a set of files for when the user is making a movie with iDVD. A copy of a user's file is typically copied into cache so that the file would not be corrupted in case of a system or application crash. Over time, caches get larger and take up more disk space. The result is that applications can slow down because they have to manage the cache. If the cache becomes too large, Mac OS X has to spend a lot of time cleaning it out. The results in the OS appearing sluggish while it is working hard to clean up. A tool like System Optimizer X cleans the cache so that the system is more responsive.

UNIX systems, including Mac OS X, have a utility called cron that allows a user to run programs at any given time when nearly any given internal. Mac OS X runs a series of scripts everyday, week, and month that perform some basic housekeeping and record gathering. By running these script using SOX, one can get a better idea of the current system state.

Running the product on late model G4 systems with at least 512 MB of RAM does not seem to speed the system up. Even on older hardware, SOX will only improve performance by a few percent. System performance is better improved by increasing RAM, CPU speed, or replacing the graphics adapter. Low end Mac OS X machines like the original G3 Macs or earlier Macs using XPostFacto to run Mac OS X would get the most mileage out of SOX. By cleaning the cache and prebinding applications, a little bit more power can be squeezed out of these older Macs.

The product documentation is light. The documentation is single README file that gives a single paragraph to what each button means. The software sells for $12 USD, which means that one is paying $2 each for 6 commands and a cron entry. The idea of a central performance tweaker is a good idea, as it simplifies the process a great deal. However, SOX does not do enough. Good additions to the program would be to allow the user to change more system settings, like disabling the spinning down of hard disks. Also, the permission fixer opens up security holes by freeing permissions on files and removing option bits. In UNIX parlance, SOX removes the t bit on the /Library/Caches directory and allow others to read the /private/var/log/wtmp file.

System Optimizer X is a utility designed to improved system performance by running a series of UNIX commands to clean the system or tweak certain OS X settings. The system improvements I experienced were very small. For RAM-starved older systems that fit the minimum requirements for Mac OS X, SOX may provide more noticeable improvements in performance. The GUI is basically a wrapper around 6 UNIX shell commands that are executed from within the application when the optimizer runs. A centralized system optimizer is a good idea, and this product has some potential, but it needs to incorporate some more useful features to warrant the shareware fee. The product could easily etch a place in a user's toolkit if the product was extended and improved significantly.


  • Easy to use interface
  • Centralized access to system optimizations
  • Very affordable
  • Displays detailed output of commands


  • Limited functionality
  • All settings/tasks can be performed without utility
  • File permission fixer creates some security risks
  • Documentation is scant and not helpful for a novice user
  • Command output would confuse novice users

Overall Rating

2 1/2 out of 5 Mice