What happened to Drupal's performance? I just installed Drupal 7 again on my cheap shared host. The installation went fine... I copied the 1098 files via FTP and installed it within 2 minutes. The standard installation (with all modules in the core) took about 5-10 seconds. After installing, the site runs well. It's a cheap hosting, so sometimes it's a little slow, but it's acceptable.

Yesterday, I've installed the new Drupal 8 (which is why I installed Drupal 7 today to compare). The first thing I noticed are the number of files: 12327. I understand modules like Views are included in the core now, but an increase of the number of files of over 10 times seems a little odd to me.Is there another reason for this?

Once I copied all files, I've tried to install Drupal 8. What a nightmare. The installation page takes up to 20 seconds to load. When I want to start the installation, I'm getting a notice OPcache is not enabled in PHP. Is this the reason for the slowness? Is there an alternative available?

Continuing the installation, I'm getting random errors. Searching for them on Google doesn't help getting me more information. Something about a fixed bug months ago, that's all I could find. I had to restart 3 times before the installation succeeded.

The biggest issue is the performance. Installing all these modules during the default installation took about 5-10 seconds in Drupal 7. It took about 20-30 minutes in Drupal 8. Okay, some more modules are included now, but this seems very odd. As I had to retry 3 times, it took me about 2 hours just to install Drupal 8. After installation, it was unusable slow, so I had to remove the whole installation.

I'm wondering if someone knows more about this issue. Does Drupal 8 require like 20 times more resources than Drupal 7 to run properly? Or is all of this because of the missing OPcache? Am I the only one with this issue?

Any advice would be welcome as I'd like to try the new features. Drupal 7 runs perfect on my cheap hosting, but Drupal 8 is a real nightmare.

I'm not sure what other technical information might to relevant to find/resolve this issue.
D8 requires more resources and yes, you should have hosting with opcache enabled, which is included by default in PHP 5.5.

Drupal 8 has so many files because it includes symfony and other projects and everything is a class.

FTP is a very bad idea for D8 and web in general in 2015. Look for a better way to do web hosting.

That said, it should not take that long. I suggest you open a bug report  and provide as many details as you can about your specific PHP version, hoster, the errors that you had, ..