2011 MBP with 8GB of RAM, generally slow under Lion, possibly thrashing

Question

I have a 17" 2011 MBP with 8GB of RAM and the fastest CPU available at the time.  It came with Snow Leopard, and it was really fast with basically everything I threw at it.
Since the upgrade to Lion, it has a general tendency to get really unresponsive.  My workload hasn't fundamentally changed.  Rather than just hope it's bugs in Lion that will get fixed, I'd like to see if anyone can advise me on things I might investigate, either to fix things myself, or to be more intelligent about identifying bugs I can report.
One thing I notice is that Time Machine backups will bring the system to its knees.  Everything will be going along just fine, and then TM will kick on, and all my apps will stop responding.  Once TM has finished, things will slowly come back to normal.  There's a lot of disk activity, which I have assumed was swapping.  Another thing that causes trouble is that mds (and a whole bunch of mdsworkers) will frequently kick on, and will slow down the system.
CPU load is always quite low, but free memory is always very low.  (However, in some OS's Free Memory is misleading, because a lot of disk blocks are cached in RAM, so it's not really "used" either..)
What I can't really distinguish for sure is if the system is slow because of swapping/thrashing (which is what I assume) or if it's slowed down for some other reason related to disk activity.
Here are the apps I typically run:
- NetBeans (which is a pig, taking up over 1GB or real memory)
- Safari (which is also a pig, often taking up more than 1GB between the main Safari process and the Web Content process)
- Sometimes Parallels (2GB for the VM, and probably another 1GB for other stuff, because it's also a pig)
- kernel_task typically reports taking up over 1GB of real memory
- WindowServer also reports using 280MB
- various other small apps like Mail, NetNewsWire, Preview, Terminal, Adium, Smultron, Colloquy, none of which use much memory
I got the 8GB, because I knew I was going to use a lot of memory for stuff, and it was great under Snow Leopard.  But with Lion, it just doesn't seem to be enough.  Even with all of those huge processes, I can't believe that their working sets are really as big as their virtual and physical memory footprints seem to be.  I mean it's not unusual for a process to have 2GB of virtual space but only a few 100MB of real memory, and some of that is shared object libraries, where the same physical memory is mapped into multiple processes.  (Have shared object libraries stopped being physically shared under Lion?)
Are other people having similar trouble?  Any suggested remedies?  Any suggestions on how to investigate so I can see if there are any actual bugs?
I would like to understand why my system went from zippy to slow after I upgraded to Lion.  Actually, quite a few things have broken.  Time Machine has become a pig, bluetooth doesn't work reliably anymore, airport doesn't connect reliably anymore, and lots of little annoying bugs.  But this is common for early point releases of new OS's, so I can't complain too much.  But for Lion to have really regressed in memory management is definitely not good.

Answer 1

Safari, for what ever reason, has become a huge memory
pig.  The longer you are using it the more memory it
gobbles up.
In Activity Monitor, check the Page outs and Swapped used.
This will tell you how much memory swapping is going on.
As for Time Machine, you may want to set your Parallels
HD image not to get backed up by Time Machine.  May
help since it is a huge collection of files.  But there have been
issues reported with Time Machine and Lion.  I don't
use it myself and opt for the cloning methodology and
seperate data backup strategy.  Also, in Spotlight
preferences under the Privacy Tab, I have added
my Windows VM folders, for same reason.  Unless you really
need to find something on the windows VM volumes when you
don't have the Windows VM active, it just eats up alot
of disk access time.
For solving airport issues check this article:
http://reviews.cnet.com/8301-13727_7-20117247-263/fixing-airport-problems-in-os- x/?tag=mncol;txt
For Bluetooth devices, try removing them, and have them rediscovered if you
can.
Hopefully, this gives you a start on cleaning things up.