Slow https(SSL) downloads and/or high CPU usage during download?
Most websites are using https by todays standards.
This mainly affects older or low-power hardware without AES-NI support — typically Intel/AMD CPUs from before 2010, or ARM-based CPUs without ARMv8 Crypto Extensions (common in older/budget NAS devices such as Synology). Note that some newer budget ARM SoCs may still lack hardware AES support, so the cutoff is less clear-cut than on the x86 side.
Hint for Synology users: You can find out your devices' CPU Architecture using this list.
This problem affects only users of older hardware. If you are using fairly new hardware, the contents of this article won't help you!
Especially modern AES GCM Cipher also suffers from known performance issues in older Java versions.
If you have an Intel/AMD CPU, you can experiment with newer Java versions (eg recent Java 1.8 or latest LTS version).
Try the following:
If that high CPU usage is caused by your CPU (missing hardware acceleration support):
All in all there isn't much you can do but for some plugins, you will find a workaround setting which lets you disable https for a particular service.
See Settings --> Plugins --> yourservice.com --> ENABLE "Prefer http over https" (or similar) or DISABLE "Use SSL/https" (or similar)
Please keep in mind that while this setting is available for some services that doesn't necessarily mean that it will actually work!
Some services drop support for http over time and enforce HTTPS. In such cases our setting won't help.
If your JD is running on a Synology NAS you might want to check out our Support forum thread regarding Synology SSL issues.
