tomcat-users mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "M. Manna" <manme...@gmail.com>
Subject Re: tomcat thread incurring CPU load
Date Tue, 19 Nov 2019 10:32:21 GMT
Mark,

On Mon, 18 Nov 2019 at 19:28, Mark Thomas <markt@apache.org> wrote:

> On 18/11/2019 14:14, Mark Thomas wrote:
> > On 18/11/2019 12:06, M. Manna wrote:
> >> Mark and others,
> >>
> >> On Mon, 18 Nov 2019 at 12:01, Mark Thomas <markt@apache.org> wrote:
> >>
> >>> OK, it looks like I can reproduce this.
> >>>
> >>> Steps to reproduce:
> >>>
> >>> - Windows 2016 Server fully patched
> >>> - Java 1.8.0u144
> >>> - Install Tomcat 8.5.45 from windows installer
> >>> - Add tcnative-1.dll (64-bit) from Tomcat Native 1.2.23
> >>> - Modify server.xml to use Http11AprProtocol on port 8080
> >>> - Make a single request
> >>>
> >>> I then see 1 core running at 100% until the connection times out after
> >>> 20s. Make another request and a core goes back up to 100% for 20s (the
> >>> default keep-alive time out).
> >>>
> >>
> >>  I have also successfully reproduced this with making a single request
> >> (sorry for not replying in the weekend). Not sure how your graph looked
> >> like, but the Jvisualvm showed me a Sinusoidal modulation curve as soon
> as
> >> the request hit the server. and it didn't go down at all.
> >
> > I see similar behaviour on Windows 7 but the the CPU usage drops after
> ~5s.
> >
> > A binary search indicates that the issue was introduced with this commit:
> >
> >
> https://github.com/apache/tomcat/commit/fffb08790e642e03f00c5f96a3a61ee09a2c8342
> >
> > (this is for 9.0.x - 8.5.x and 7.0.x had similar commits)
> >
> > However, that code was removed when APR was switched to a single poll
> > set.
>
> Ah ha. It was removed in 9.0.x but not in 8.5.x (only 9.0.x switched to
> a single Poller) so it does look like this change is responsible.
>
>  Thanks for Debugging this. Are you saying that we will have a patch for
this? If so, which jar could we replace in 8.5.45 until
we move to new tomcat?

Thanks,


> Mark
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: users-unsubscribe@tomcat.apache.org
> For additional commands, e-mail: users-help@tomcat.apache.org
>
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message