Drupal Solr Remaining is wrong. Why? Using the Drupal Solr admin UI I indexed all queued content.
However, even if everything is indexed and searchable, it indicates, as seen below, that only 2% has been indexed!

Indexed         31084 Items (934.03 MB on disk)
Remaining   30597 items (2% has been sent to the server)
Schema          drupal-4.1-solr-3.x

The problem is that when I want to index the remaining, it starts from zero.
Why is that? Is it a bug?
Indexing is done during cron runs. When you've set up indexing, don't ask for it to be indexed again, unless you want it to start from scratch.

If you want to increase the percentage, and don't want to wait for the next scheduled cron run, run cron manually by navigating to Home » Administration » Configuration » System  » Cron and press Run cron.

If you want to automate this, set up an external cron and trigger it every 10 minutes until indexing is done.

There is no setting to index everything instantly. If that is what you want to do, the answer is that this is not possible. You have to be patient. The reason there is no such setting is because that would put a too heavy load on your system. The system is designed to work the way it works for a reason.