400 000 products in DB, 5GB from ram and 5000req/s

Hi, I have a big problem. My shop has 400,000 products. If i try load web. First request take long 5 minutes.
This is ram usage http://d.pr/i/qFIJ and database requests http://d.pr/i/bSWx
Web is dead. Anything that takes a long time.
Is there any way to fix it? Rewrite DAL to dapper?

My HW:
CPU xeon Intel Six-Core XEON X5660
HDD : 6 x 1TB 10 000 rpm velociraptors, data, log, temp db on each RAID1
32GB ram kingston ECC

Unanswered post is killing me on this forum.

What version of nopCommerce?

Be sure to turn off
Settings -> Catalog settings -> Show the number of distinct products besides each category + Include subcategories (number of distinct products):

Have you searched the forums?  (There have been many discussions about performance)

nordic wrote:

Please let me know if you resolve this issue. I'm eventually going to be putting around 150k products on nop and I hope it performs well.

This is unbelievable!!!!. Why not reply maker nopCommerce??!!

I can tell you that EF is the culprit here.
Changing EF overnight is not the right answer here. Profile the query that is taking longer and re-write that piece using optimized plain old TSQL. You also might want to take a look at the indexes on those tables.
Entity craps out with large datasets.

amassani wrote:

I agree with you. Moreover, you may like to try nopAccelerate. It can make you scale very easily with more products and many concurrent visitors. Let me know if you would like to try.