Zigzag download pattern explained

wiki/advanced/zigzag-download-pattern.md

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+ # Zigzag download speed pattern
+
+## Sympton
+
+SABnzbd can show a zigzag download pattern like in the screenshot:
+
+<img width="662" height="77" alt="image" src="https://github.com/user-attachments/assets/39a0cff7-9506-47f1-8a4b-b414c4781d07" />
+
+## Cause
+
+This is caused by a disk that is slower than the Internet newsserver download speed.
+
+Easy check: after downloading and seeing the pattern, in SABnzbd's upper right corner, click on the wrench symbol ("Status and interface options"),
+then click on first tab Status. Check if you see "**Download speed limited by Disk speed** (...x)". If that line is there, it's proof your disk is the bottleneck.
+
+Then: in the same window, and there click on the Refresh Circled Arrow. After 10 seconds, in the lower part you will see the hardware performance and Internet speed.
+
+Example of a low spec machine (slow disk for Complete folder, low pystone value):
+
+<img width="645" height="224" alt="image" src="https://github.com/user-attachments/assets/96517d39-d5f7-45ea-bec2-df668471d3a9" />
+
+
+## Explanation:
+1. The first downloaded parts are cached into RAM, which is fast.
+2. In the background, SABnzbd & OS is writing from RAM to disk.
+3. However, if the disk cannot keep up, RAM fills up, and SABnzbd can only throttle the download speed (which you see in the graph)
+4. As soon as the cached data is written to disk, there is RAM available, and SABnzbd can speed up again.
+5. ... until RAM gets filled up again due to the slower disk, and the process repeats itself, causing the zigzag pattern.
+
+
+## Solution
+
+Get a faster disk until you no more get "Download speed limited by Disk speed (...x)"
+
+And on more difficult setups like Unraid: consult Unraid documentation.

wiki/advanced/zigzag-download-speed.md

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+# Zigzag download speed pattern
+
+## Sympton
+
+SABnzbd can show a zigzag download pattern like in the screenshot:
+
+<img width="662" height="77" alt="image" src="https://github.com/user-attachments/assets/39a0cff7-9506-47f1-8a4b-b414c4781d07" />
+
+## Cause
+
+This is caused by a disk that is slower than the Internet newsserver download speed.
+
+Easy check: after downloading and seeing the pattern, in SABnzbd's upper right corner, click on the wrench symbol ("Status and interface options"), 
+then click on first tab Status. Check if you see "**Download speed limited by Disk speed** (...x)". If that line is there, it's proof your disk is the bottleneck.
+
+Then: in the same window, and there click on the Refresh Circled Arrow. After 10 seconds, in the lower part you will see the hardware performance and Internet speed.
+
+Example of a low spec machine (slow disk for Complete folder, low pystone value):
+
+<img width="645" height="224" alt="image" src="https://github.com/user-attachments/assets/96517d39-d5f7-45ea-bec2-df668471d3a9" />
+
+
+## Explanation:
+1. The first downloaded parts are cached into RAM, which is fast. 
+2. In the background, SABnzbd & OS is writing from RAM to disk. 
+3. However, if the disk cannot keep up, RAM fills up, and SABnzbd can only throttle the download speed (which you see in the graph)
+4. As soon as the cached data is written to disk, there is RAM available, and SABnzbd can speed up again.
+5. ... until RAM gets filled up again due to the slower disk, and the process repeats itself, causing the zigzag pattern.
+
+
+## Solution
+
+Get a faster disk until you no more get "Download speed limited by Disk speed (...x)"
+
+And on more difficult setups like Unraid: consult Unraid documentation.