Edit: In order to solve it I decided to try PHP-FPM. It gave me a headache, but now it works faster and wastes WAY less memory (now it stays arround 200 MB down from almost 1,5 GB). Perhaps we just should avoid modphp, these days..._
I've been researching although I can't find a solution. Well, I have a VPS, 3 processors, 30 GB of storage and 1,5 GB of RAM. Pretty odd, it seems, but it's because I took a bit of my available resources to create a backup DNS server. But as I've already ran OwnClound on my Raspberry Pi, it woudln't be hard for it to run in a server of such configurations as of my VPS.
Except it is. I'm using Apache Event MPM and memory usage is blowing up to near 100%. But it won't stay this way, as the time passes, the machine goes more and more clogged until it becomes imposible even logging into it via SSH.
Well, there's a plenty of RAM, I think, as I'm the only user (I'm using it for keeping my own stuff). Is there any way of tunning it?
Server configuration
Operating system: Debian 8
Web server: Apache 2.4.23
Database: MySQL 5.7
PHP version: 7.0.14
ownCloud version (see ownCloud admin page): 9.1.3
Updated from an older ownCloud or fresh install: Fresh install
Special configuration (external storage, external authentication, reverse proxy, server-side-encryption): no
ownCloud log (data/owncloud.log)
{"reqId":"h1i7Nwz9HzG\/OvYSEXcC","remoteAddr":"177.32.7.31","app":"core","message":"Login failed: 'prppedro' (Remote IP: '177.32.7.31')","level":2,"time":"2017-01-15T06:16:25+00:00","method":"PROPFIND","url":"\/owncloud\/remote.php\/dav\/","user":"--"}
{"reqId":"dyKahC7U85xcT2khC4Nt","remoteAddr":"177.32.7.31","app":"core","message":"Login failed: 'prppedro' (Remote IP: '177.32.7.31')","level":2,"time":"2017-01-15T06:16:50+00:00","method":"PROPFIND","url":"\/owncloud\/remote.php\/dav\/principals\/users\/prppedro\/","user":"--"}
{"reqId":"sS2q5VJo4M\/+kBync0Ro","remoteAddr":"177.32.7.31","app":"core","message":"Login failed: 'prppedro' (Remote IP: '177.32.7.31')","level":2,"time":"2017-01-15T06:18:46+00:00","method":"PROPFIND","url":"\/owncloud\/remote.php\/dav\/principals\/users\/prppedro\/","user":"--"}
{"reqId":"6\/wx2iiWNcTD7K7jerjz","remoteAddr":"177.32.7.31","app":"PHP","message":"Out of memory (allocated 4194304) (tried to allocate 32768 bytes) at \/usr\/local\/apache2\/htdocs\/owncloud\/apps\/federatedfilesharing\/lib\/RequestHandler.php#511","level":3,"time":"2017-01-15T07:23:34+00:00","method":"GET","url":"\/owncloud\/ocs\/v2.php\/apps\/notifications\/api\/v1\/notifications?format=json","user":"prppedro"}
{"reqId":"ElbFcEtG4NTSzYM3Aj1w","remoteAddr":"177.32.7.31","app":"caldav","message":"Exception: {\"Message\":\"HTTP\\\/1.1 501 There was no handler found for this \\\"GET\\\" method\",\"Exception\":\"Sabre\\\\DAV\\\\Exception\\\\NotImplemented\",\"Code\":0,\"Trace\":\"#0 \\\/usr\\\/local\\\/apache2\\\/htdocs\\\/owncloud\\\/3rdparty\\\/sabre\\\/dav\\\/lib\\\/DAV\\\/Server.php(248): Sabre\\\\DAV\\\\Server->invokeMethod(Object(Sabre\\\\HTTP\\\\Request), Object(Sabre\\\\HTTP\\\\Response))\\n#1 \\\/usr\\\/local\\\/apache2\\\/htdocs\\\/owncloud\\\/apps\\\/dav\\\/appinfo\\\/v1\\\/caldav.php(83): Sabre\\\\DAV\\\\Server->exec()\\n#2 \\\/usr\\\/local\\\/apache2\\\/htdocs\\\/owncloud\\\/remote.php(164): require_once('\\\/usr\\\/local\\\/apac...')\\n#3 {main}\",\"File\":\"\\\/usr\\\/local\\\/apache2\\\/htdocs\\\/owncloud\\\/3rdparty\\\/sabre\\\/dav\\\/lib\\\/DAV\\\/Server.php\",\"Line\":462,\"User\":\"prppedro\"}","level":4,"time":"2017-01-15T19:07:09+00:00","method":"GET","url":"\/owncloud\/remote.php\/caldav\/calendars\/prppedro\/personal","user":"prppedro"}Integrity status for oC9+
No errors have been found.Thanks,
Att.,
t.r.p.