The NTFS file system likes to cache files that are open in physical memory for the
fastest possible access to the raw data. This is accomplished by first reading the
data from the hard drive and transferring it to physical memory. Depending on
the amount of RAM in your computer, portions of the open files may be paged to
disk in the paging file because the entire file cannot fit in the available physical
memory. This results in slower overall performance because for an application to
read the entire file, existing data in the physical memory cache has to be paged
back to the hard disk to make room and then other unread portions have to be
pulled back from the hard drive into physical memory. This carefully orches-
trated memory swap requires a lot of CPU, memory, and hard drive processing
time. Whenever memory paging occurs, it slows down the overall performance
of your computer.
If you use your computer for anything that requires fast reads of hundreds of
files, such as indexing your MP3 collection, you might notice that it takes your
computer a while to read these files. This is because the file system has only a
certain amount of physical and paging file space allocated to it, which results in
increased paging activity. Depending on the amount of physical memory in your
computer, you might be able to get away with increasing the memory allocated
to the NTFS file system on your computer. This will increase the performance
of high disk read operations.
Before you get started, you need to analyze the available physical system
pool memory on your hardware. Increasing the NTFS memory allocation on
a machine without enough of the right type of free memory will result in a
decrease in overall system performance because other system components have
to use less memory, which can increase paging.
Follow these steps to determine whether you can increase the memory
allocation:
1. Click the Start button, type perfmon in the Search box, and then
press Enter.
2. When the Performance Monitor loads, click Performance Monitor under
Monitoring Tools.
3. Click the chart and press Ctrl+I to add performance counters.
4. Navigate to the Memory section and expand it.
5. Locate and select Cache Bytes Peak and press Add.
6. Locate and select System Cache Resident Bytes and press Add.
7. Press OK when both counters are added.
8. Switch to the Report View by pressing Ctrl+G until you see the perfor-
mance counters listed, as shown in Figure 14-3.
9. Note the values of all three counters on a sheet of paper so that you can
refer to them even after a reboot.
Now you need to analyze the counters you just gathered. Cache Bytes Peak
shows the maximum amount of physical system pool non-page memory in use
since your computer was last rebooted. This number is very important because
the memory manager in Windows 7 limits you to 256MB (268,435,456 bytes) of
physical system pool non-page memory regardless of the amount of RAM in
your computer. If your Cache Bytes Peak value is within 20MB of the 256MB
limitation, this is a big red flag not to attempt this hack. In that scenario, you
might slow down your computer even more by implementing this hack.
Next, let’s take a look at your total System Cache Resident Bytes. This is the
current size of the file system cache in physical system pool non-page memory.
When you implement this hack, the value can increase by up to 50 percent. Take
50 percent of the System Cache Resident Bytes value and add it to the Cache
Bytes Peak value. Make sure that it is less than the 256MB limit.
If your results of the two previous tests are on the borderline for passing, you
should still implement this hack. It is easy to undo this setting and it will not
harm any of your hardware or have a permanent effect on the performance of
your computer.
Follow these steps to increase the memory available to the file system:
1. Click the Start button, type Command Prompt in the Search box.
2. Command Prompt appears at the top of the list in your Start menu. Right-
click the shortcut and select Run as Administrator.
3. After Command Prompt has loaded in the Administrator context, you can
access the NTFS configuration utility. At the prompt, type fsutil behavior
set memoryusage 2.
4. Close Command Prompt and restart your computer to activate the
change.
After your computer has restarted and you have loaded your usual applica-
tions, check to make sure that your Cache Bytes Peak value in Perfmon is still less
than 256MB. Also find the difference between your new System Cache Resident
Bytes value and the value before the change. Add that to the old Cache Bytes Peak
value you wrote down earlier to ensure that the sum is also less than 256MB.
If it is greater, you might be stealing memory from other system components,
resulting in an overall slowdown in performance.
If you notice any decrease in performance or have bad results from the pre-
ceding test, undoing the change is very simple. Just type fsutil behavior set
memoryusage 1 at the prompt instead and reboot.
fastest possible access to the raw data. This is accomplished by first reading the
data from the hard drive and transferring it to physical memory. Depending on
the amount of RAM in your computer, portions of the open files may be paged to
disk in the paging file because the entire file cannot fit in the available physical
memory. This results in slower overall performance because for an application to
read the entire file, existing data in the physical memory cache has to be paged
back to the hard disk to make room and then other unread portions have to be
pulled back from the hard drive into physical memory. This carefully orches-
trated memory swap requires a lot of CPU, memory, and hard drive processing
time. Whenever memory paging occurs, it slows down the overall performance
of your computer.
If you use your computer for anything that requires fast reads of hundreds of
files, such as indexing your MP3 collection, you might notice that it takes your
computer a while to read these files. This is because the file system has only a
certain amount of physical and paging file space allocated to it, which results in
increased paging activity. Depending on the amount of physical memory in your
computer, you might be able to get away with increasing the memory allocated
to the NTFS file system on your computer. This will increase the performance
of high disk read operations.
Before you get started, you need to analyze the available physical system
pool memory on your hardware. Increasing the NTFS memory allocation on
a machine without enough of the right type of free memory will result in a
decrease in overall system performance because other system components have
to use less memory, which can increase paging.
Follow these steps to determine whether you can increase the memory
allocation:
1. Click the Start button, type perfmon in the Search box, and then
press Enter.
2. When the Performance Monitor loads, click Performance Monitor under
Monitoring Tools.
3. Click the chart and press Ctrl+I to add performance counters.
4. Navigate to the Memory section and expand it.
5. Locate and select Cache Bytes Peak and press Add.
6. Locate and select System Cache Resident Bytes and press Add.
7. Press OK when both counters are added.
8. Switch to the Report View by pressing Ctrl+G until you see the perfor-
mance counters listed, as shown in Figure 14-3.
9. Note the values of all three counters on a sheet of paper so that you can
refer to them even after a reboot.
Now you need to analyze the counters you just gathered. Cache Bytes Peak
shows the maximum amount of physical system pool non-page memory in use
since your computer was last rebooted. This number is very important because
the memory manager in Windows 7 limits you to 256MB (268,435,456 bytes) of
physical system pool non-page memory regardless of the amount of RAM in
your computer. If your Cache Bytes Peak value is within 20MB of the 256MB
limitation, this is a big red flag not to attempt this hack. In that scenario, you
might slow down your computer even more by implementing this hack.
Next, let’s take a look at your total System Cache Resident Bytes. This is the
current size of the file system cache in physical system pool non-page memory.
When you implement this hack, the value can increase by up to 50 percent. Take
50 percent of the System Cache Resident Bytes value and add it to the Cache
Bytes Peak value. Make sure that it is less than the 256MB limit.
If your results of the two previous tests are on the borderline for passing, you
should still implement this hack. It is easy to undo this setting and it will not
harm any of your hardware or have a permanent effect on the performance of
your computer.
Follow these steps to increase the memory available to the file system:
1. Click the Start button, type Command Prompt in the Search box.
2. Command Prompt appears at the top of the list in your Start menu. Right-
click the shortcut and select Run as Administrator.
3. After Command Prompt has loaded in the Administrator context, you can
access the NTFS configuration utility. At the prompt, type fsutil behavior
set memoryusage 2.
4. Close Command Prompt and restart your computer to activate the
change.
After your computer has restarted and you have loaded your usual applica-
tions, check to make sure that your Cache Bytes Peak value in Perfmon is still less
than 256MB. Also find the difference between your new System Cache Resident
Bytes value and the value before the change. Add that to the old Cache Bytes Peak
value you wrote down earlier to ensure that the sum is also less than 256MB.
If it is greater, you might be stealing memory from other system components,
resulting in an overall slowdown in performance.
If you notice any decrease in performance or have bad results from the pre-
ceding test, undoing the change is very simple. Just type fsutil behavior set
memoryusage 1 at the prompt instead and reboot.
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