Hello,
swappiness = 60 is the standard value
i thought 60 was recommended for server installs on ubuntu... (Which is why it's the default).
It is much more the "default" than the "recommended" setting. IMO, "Recommended" is what you need it to be depending your computer vocation.
I though however that swappiness value was only reflecting how Ubuntu will be prone to swap or not but not reflecting whenever some swap occurs
As far that my understanding of it goes, yes, that is totally correct.
According to the official Ubuntu Website:
The default setting in Ubuntu is swappiness=60. Reducing the default value of swappiness will probably improve overall performance for a typical Ubuntu desktop installation. A value of swappiness=10 is recommended, but feel free to experiment.
ref:
https://help.ubuntu.com/community/SwapFaqWith that said;
For desktops or database servers, IMO, swappiness = 10 is the configuration that work the best (try running Chrome or Firefox while swapping -> Only do it if you like "grayed, static, non-responsive windows"

).
We must keep in mind that swap = drive use. HDD and SSD are slow memory. RAM is much more fast.
IMO, caching a database in RAM is a smarter aproach since it is less using/putting pressure on physical drives. This also comes from the fact that logs requires a lot of read/write on a physical device. The selected media used mathers.
Short story;
Load balancing the hardware ressources simply makes everything run faster.
Some other thinking;
This of course leads me to believe manage-logs is running tons of mysql queries as mysql might be 90% cpu while manage-logs is 10-20% at the same time.
When CPU is toping up, usually, this mean that there is "things to be done" waiting in the CPU queue. If you are swapping, this is an even more common scenario (hard drives are busy handing or writing things. Either on the swap partition, in your logs or in your DBs.).
That multi-tasking philosophy is driving a lot of server administrators to dedicate a full HDD or SSD for the swap.
Swap comes into play but as effect, not cause, in this particular case, I think.
Well, yes and no... When swap comes into play, things will just go worst and worst and worst and ... (hard drives are kinda slowing their response time down so getting less things done - downward spiral scenario)
One last thing;
Try checking your logging policies. Being to much of a "big brother" will slow you down.
[Off Topic]And in my case, the longer the uptime, the longer manage-logs hogged resources. Eventually, it ran continually.
You can do better - garanteed!
My Zentyal 2.0 multi tasking home server build on a 4X WD Green 5400RPM soft RAID10/RAID1 (the full 2.0 setup except the PBX side that was replaced by FreePBX + much hacking on top of it like suPHP and a rethinked FTP module) had only very few reboots (once every power failure). The Zarafa indexer is the only thing that chews up 50% of my AMD 5400 dual core. And on top of that, it does have a total of 2GB of RAM.
[/Off Topic]I hope this will help
Best,
Marcus