Keep in mind that the thing that will impact your download speeds the most is your Usenet provider.  Unlimited speeds and plentiful connections are the foundation for high-speed downloads.

NZBGet can be fine-tuned for your specific hardware, software, and internet connection combination, although it may take some experimentation.  Review these 3 main performance-impacting factors:

• CPU speed - The number of connections, encryption, unpacking and par checks.
• Available RAM - Cache and buffer settings
• Hard drive interface - Hard drive performance will be limited by the number of simultaneous operations it can perform.

Reviewing the below settings and experimenting with your specific setup can improve performance.

Please Note: It is highly suggested to create a backup of your current settings before making any changes.

CPU Speed

Encrypted communication
The Server.Encryption setting is an on/off option found in the News Server settings section.  Deactivating the server encryption can improve performance.  More advanced users can use the option Server.Cipher to fine-tune the TLS/SSL settings.  Review the NZBGet article on choosing a cipher for more information on cipher selection and implementation.

Number of connections
The Server.Connections settings are in the News Server menu and are set server by server.  For your primary servers (those set to Level 0) use as few connections as possible, but use no less than 20 as a minimum.  Any backup servers should also be set to the same number of connections that you have your primary server’s connection count set to.

CRC check
To reduce CPU overhead, deactivate CrcCheck found in the Check and Repair section. Please be aware that disabling CrcCheck makes quick par-verification less reliable and can occasionally result in a full verification being required.

Par check
Par check is a demanding process for CPUs but can be optimized.  All of the below settings are found in the Check and Repair section.

1. ParCheck: Auto
2. ParScan: Auto
3. ParQuick must be on if you have fast par-verification active
4. ParThreads uses multiple CPU cores. If set to 0 this will use all available CPU cores.
5. ParBuffer: increase as memory allows
6. Activate the ParPauseQueue setting to prevent downloading and Par checking from happening at the same time.
7. ParTimeLimit places an upper limit on the amount of time NZBGet will attempt to repair a file.
8. ParRename: activate to handle misnamed files, this is recommended if Unpack is disabled.

Unpack
Activating UnpackPauseQueue, found in the Unpack menu, will prevent simultaneous downloading and unpacking limiting CPU usage.

Download speed limit
Use of the DownloadRate setting, found in the Connection settings, will add additional CPU overhead.

RAM settings

Article cache
The ArticleCache settings, found in the Download Queue menu, can improve your unpack speed.  If you are using the DirectWrite option, set your article cache to 200 MB.  If DirectWrite is disabled, use a larger cache (up to 1GB).

Write buffer
The WriteBuffer setting (also found in the Download Queue menu) should be dependent upon available system RAM.  If you have a lot of available RAM ,set it to 1024.  If you have a limited amount of RAM available, set it to 32.

Hard drive settings

Direct write
The DirectWrite option, found in the Download Queue menu, does not support HFS+ formatted disks (Mac OS) and will need to be deactivated.  Please note that if deactivated, a large article cache must be configured for best performance (see Article Cache above).

File fragmentation
Activating WriteBuffer and ArticleCache, both found in the Download Queue menu, can help minimize file fragmentation and improve post processing performance.

Drive cache flushing
If you experience slowdowns during queue flushing, we suggest deactivating the FlushQueue setting found in the Download Queue menu.  If you do not see improvement in your speeds, turn it back on.

Logging
You can deactivate the error logging functions of WriteLog, found in the Logging menu.

Par check and unpack
The options of ParPauseQueue (Check and Repair menu) and UnpackPauseQueue (Unpack menu) can be turned on to prevent simultaneous disk access by the downloading, par-checker, and unpacker functions.  These options are off by default.