You must have taken these most recent screenshots/statistics on your firewall (not SMS as mentioned earlier in this thread) or you are running standalone. You may want to start a different thread to avoid confusion as use of memory is quite different on a SMS vs. firewall.
wstlsd handles HTTPS negotiations associated with HTTPS Inspection (if enabled) or the "Categorize HTTPS Sites" checkbox if it is set. It is normal for these processes to use a fair amount of memory. There are two of them so it appears you have 2 Firewall Worker cores, which probably indicates your firewall has a total of 2 physical cores (at least with the default settings). I'm guessing you have a 5100-5400, please confirm.
You have 8GB of RAM being reported, please confirm that Gaia is running in 64-bit mode.
The 1385 being reported by free -m indicates that at some point the firewall dipped into swap space (probably during a policy install) but does not mean the firewall is actively swapping right now (wa being 0.0% is a good indication that it is not). Use sar -W to determine this for sure, and please see my posts about it in this thread:
Healthcheck script results
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