Quick checks aren't super helpful, but they can test random stuff
a bit, so let's keep them, but make them smaller. Also, let's cram
the random selections into the first quarter of a shard so we see
more container updates to fewer containers because that's probably
more interesting.
i used this script, a little clunky but it got the job done
```bash
for file in `find . -type f -print | grep '\.go'`; do
sed '1,/^\/\/ limitations under the License.$/d' $file > $file.tmp;
result=`cat $file.tmp`
if [[ result != "" ]]; then
gofmt $file.tmp &> /dev/null;
if [[ $? == 0 ]]; then
mv $file.tmp $file && gofmt -w $file;
else
rm $file.tmp;
fi
else
rm $file.tmp;
fi
done
```
In nearly all cases, we can just switch ioutil.TempDir->testhook.TempDir
and similarly for TempFile. There's one case where we can't because we
need files to be removed before tests are over.
Also in the process give identifiable names to a lot of temporary files
and make sure they're being cleaned up, and don't use "/tmp/foo" as a
file name in a test that could be running in more than one test process
at once. :)
- fix a bug in computing leafCell.BitN in a run after a bit Remove
- shrink bitmaps on remove
- util_test.go has Cursor.DebugSlowCheckAllPages to verify;
used by cursor_test.go
This commit changes the checkpointing to determine a minimum WAL ID
for readers and a max ID based on the writer. Pages are checkpointed
from the WAL up to the writer's max WAL ID but segments are removed
only up to the reader's minimum WAL ID. This ensures that WAL pages
are not removed out from under current read transactions.