performance is extremely slow on a 2 core 64bit laptop with 4GB ram? how can I troubleshoot?

You've weren't specific as to what release; but the *latest* is the Lubuntu 22.10 or 2022-October release so I'll assume that. As `firefox` is now a *snap* package, it's stored in a *squashed* format on disk which takes time to decompress; but this is only required on first run (*which will differ to 19.04 or 18.04 LTS being the last two that ran on a pentium M*). Did you adjust SWAP to something matching your usage? as the default install options can result in NO swap or only 512MB which is very limited on older hardware & you get much better performance if it's increased as per Lubuntu docs

Some pages that you may find helpful - https://discourse.lubuntu.me/t/swap-and-lubuntu-faq/2591 , https://discourse.lubuntu.me/t/how-to-create-a-swapfile-in-lubuntu-20-04-20-10/1959 . You mention potential faulty RAM, why not boot & run RAMtests on your hardware? rather than just pull out ram modules... FYI: *I had a box which had 8GB of RAM (core2quad) that was I stole half of the RAM to test in another box I suspected had issues; I didn't expect to notice a difference with only 4GB of RAM given how I used the box; but I sure did!! Adding/increasing swap size fixed this however in secs*.

@guiverc its not just loading Firefox that is slow. it is any command or app. takes several seconds to open any window. I pulled out the ram modules one by one because another user suggested that. can you tell me which Ram test you would recommend me to run .

@guiverc I also followed your suggestion to increase the swap space. I raised it to 4GB from 1GB but that does not seem to improve the horrible sluggishness

I just use the RAM tester on the Lubuntu media; eg. on the manual https://manual.lubuntu.me/stable/1/1.3/installation.html (that link is for the latest *stable* release which is 22.10) you'll see a *TEST MEMORY* as the third option available; I usually use that! Note: your hardware will dictate what options you see, with some hardware causing the ramtest option to be excluded for legal reasons (*it can't be run unless specifically downloaded/installed/run by end-user so it won't appear as option if your hardware is of that type*) so not everyone sees the same options, but it's what I'd use

You've not provided release specifics, but as stated *snap* packages are stored in a *squash* format on disk for recent releases as Mozilla packages their `firefox` now as a *snap* package; which is slower due to extra expansion that was not required to older releases that stored a *deb* unsquashed on disk (*using more disk space in that case; terms like 'latest' mean nothing to me as 75% of users on this site disregard many releases; 22.10 is our latest 'stable' release of Lubuntu*). Without specifics I'm forced to be somewhat *generic*.

FYI: Your comparison with pentium M is *vague* and unspecific too... I can boot a Lubuntu 19.04 release on a pentium M device here, they are both running LXQt though of course but very different versions & they have different stacks due to age, but is that what you're comparing it to?? or something very different (eg. a prehistoric & very different LXDE product for example which uses much *simpler* & *deprecated* GTK2 stack that has far fewer features (*making it lighter & security risk etc*) & not really comparative... Please try and be specific if you wish details to be understood.

@guiverc thanks . i will repost my question and try to provide the info you suggest

You don't need to repost; edit your question & provide additional details there.

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