I have particular problems with WFE performance during search jobs. Our farm contains 1 app server, 1 db server and 2 identical WFE servers (NLB) - really identical, checked 5 times already. However I try to distribute search components through farm (query & crawl on WFEs, crawl on app, queries on WFEs, one WFE failover only etc.) we always have one of our WFE overloaded. Since we added Project Server and one of our SC overcomming the 64K limit of ACL (known issue), inc. jobs running about 10 times slower than usual and because users are enable to work with portal on the affected server during this jobs, it is really an (annoying) issue. I'm force to plan jobs during night and this is not enough.
I know, that crawler no longer stores a copy of an index, items are being directly propagated to a query server, but how it is possible that one of them is completely overloaded during all jobs? Just only one of two? Network, drives, dbs, all other counters are "in green numbers".
The only and last thing what we did not tested yet is third server installation just for search only. And my managers don't want to hear a word about it.
[edit #2 beter perfmon counters, administrative reports]
One realy long crawl - all on STS4
Thank you for any advice.