Enhancement/improved user scheduler

[DnlLrssn]

Checklist

• [x] tests added
• [x] commits conform to the Commit message format
• [ ] documentation updated

Squash commit message

• Increase buffer size for logchan
• Use timer instead of time.After to decrease time to GC (can be GC'd after .Stop is called)
• Improved scalability of user session creator loop

Info

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