Fix a comment: __evict_get_page is not the only place the page's ref
state is set to WT_REF_LOCKED for eviction, don't imply it is.
It is okay for checkpoint reads to see a page that is discarded in the live system.
Ignoring return value of function '__wt_event_handler::handle_close'.
Ignoring return value of function '__wt_event_handler::handle_close'.
c07dca7 removed the code to free the hazard array when closing the
list of sessions, remove the comment to match.
Merge branch 'develop' into block-diag-fix
Minor restructuring, don't reach through the session handle to figure out
if we're dealing with a read-only (checkpoint) handle.
Merge pull request #741 from wiredtiger/block-diag-fix

Diagnostic fix for checkpoint reads
Don't call checkpoint-unload on checkpoint-load error; unload does
things like truncate the file, and if we fail early enough to have
not yet initialized the checkpoint, really bad stuff would happen,
including data corruption.
Clarify a comment.
Update comments around auto-close callbacks.
Salvage can read through the standard WT_BM handle when reading overflow
items, so it's necessary to test if we're performing salvage, overflow
blocks might be long gone.
If a file is checkpointed without a previous checkpoint having been
"resolved", do the resolution internally so we don't leak blocks.
It's marginally safer to leak the blocks, but there has to be a bug
in the upper layers for this to happen at all, and leaking blocks
means file verify will fail.

Add messages to complain if we see this problem happen.
Fixes for overflow caching with fast-path eviction.

This refines the changes in 1bb1074495f21f4aab8058aaf80b4d3a5a0c2801 to only apply when safe, which means both that the transactional context is "good enough", and that the page is simple.  Otherwise, we need a real transaction.

refs #743
There's no need to set the page's read generation inside the eviction
lock: I can't imagine it makes a difference, but we know the read
generation is a hot cache line, don't mix-and-match.
Fix compiler warnings with GCC 4.7.2 on Ubuntu.
Allow wtperf to have a zero runtime.

It can be useful to re-use of a populate across multiple runs, or
sometimes the populate phase is what we're interested in.
Do a full-barrier when spinlock logging is configured, it cuts down on
the number of races.

Add statistics to track the number of spinlock acquisitions.
Make memory statistics sort together, get rid of most of the uses of
"total", it doesn't add information for connection-only statistics.
lint, cleanup, style.