macbook pro 13 inch mid 2012 using el capitan

It will work fine with EC is you have enough memory. I say at least 8 GB is necessary. 4GB is very marginal.

To check compatibility of apps see:

https://roaringapps.com/apps

I have an Early 2011 Macbook Pro.

I upgraded from Mavericks to El Capitan 10.11.2 and had no speed issues. I found that if I looked at memory usage with Activity Monitor, that the memory usage went down when I switched to El Capitan.

After upgrading to El Capitan I upgraded my memory from 4 GB to 8 GB but did not notice much of a speed increase.

But then I upgraded my hard drive to a Samsung 850 EVO 500 GB SSD drive and noticed a huge speed increase.

So don't be afraid to upgrade to El Capitan, but if you are looking for an upgrade I would suggest upgrading both memory and also hard drive to SSD.

Kim

Using almost all the memory is normal. Unused memory serves no use. So OSX caches files that might be used in order to possibly speed up things since reading from memory is faster than reading from disk

Your free memory is probably being used as a cache to improve performance, I would not worry about it.

Most apple macbook pros come with 4 GB of memory, so you have twice that much.

If you have 8 GB of memory you should have no problem upgrading to El Capitan.

Every time a new OX comes out some programs may require an update.

I use Carbon Copy Cloner and they came out with a new version to work with El Capitan.

You can check online to see if all the programs you use are compatible. https://roaringapps.com/apps?platform=osx

I have had no problems with El Capitan. One of the reasons I upgraded was for the new Photos app.

Kim

My 2012 13-inch 2.5ghz Core i5 non-Retina MBP is happily running El Cap. I had upgraded to 8GB RAM while still running 10.9 Mavericks not because the computer was slow but because my favorite RAM vendor put suitable RAM on sale. My son has exactly the same model and OS but with the original 4GB RAM and, when i check his memory pressure and swaps with Activity Monitor, it shows no stress.

You mileage may vary, especially if you came from the Windows World where every user has been cleverly brainwashed into believing you must have steaming piles of third-party security and cleaning apps installed. If you come to Mac with this mindset, you will be treated to poor performance. So many reports of slow Macs here are traced to exactly the kind of unneeded software that Windows users claim they can't compute without. Let you Mac be a Mac. Or, As they say in rural Idaho, "Don't hitch a race horse to a plow and expect it to win!"