Can you reproduce using the real network driver? The loopback/localhost interface is famously junk. On Jun 10, 2015 11:22 AM, "Andy Wang" <aw...@ptc.com> wrote:
> Yeah, that much I more or less get. > > What I really don't understand is what can a client do (IE11) that would > regularly cause httpd.exe to hang with AcceptEx. This is reproducible on > every single machine I've ever tried, including completely vanilla virtual > machines, or pretty straightforward physical machines with intel NICs and > no additional stack drivers. That seems like a pretty hideous architecture > if a regular non-malicious client requests could end up causing the web > server to simply stop responding. > > The InstallAnywhere problem I mentioned is also reliably reproduced on > every single Windows system I've tried this on (about a dozen different > systems with different configurations - virtual and physical). This is the > one I especially can't understand. How would launching httpd.exe from a > installer process (java.exe specifically) prevent it from responding to > requests. > > Andy > > On 06/10/2015 10:48 AM, William A Rowe Jr wrote: > >> It turns off all advanced socket mechanics for accepting connections. >> That means >> it won't pre-fetch data. Because of how cobbled-together the WinSock >> network >> stack drivers (third parties, included) were, there are many things that >> break >> sendfile (disable sendfile) or socket reuse (disable advanced accept >> logic). >> >> In other words, if you need reliability on some pretty crazy >> installations of >> Windows with lots of out-of-date drivers, your solution is the way to >> go. They >> are for performance, there is no reason to turn these on in low-traffic >> cases. >> >> >> On Wed, Jun 10, 2015 at 10:31 AM, Andy Wang <aw...@ptc.com >> <mailto:aw...@ptc.com>> wrote: >> >> I originally asked this on user@httpd and didn't get a response, so >> thought I'd redirect to dev and see if anyone can explain why this >> would occur if you have time. I have to admit, it's a curiosity to >> me, that I just don't want to let go until I understand it and what >> research I've done into AcceptEx doesn't seem to be giving me any >> more insight. >> >> --- original message --- >> >> We've come across numerous cases where apache httpd 2.4 (I'm using >> 2.4.12 but I don't believe this is version specific) hang using the >> default configuration options. >> >> There are two cases >> 1) we have an InstallAnywhere installer that launches httpd during >> install time to do some initial work. When the installanywhere >> installer starts httpd.exe (it does it via cmd.exe) httpd does not >> respond to requests. If you kill the installanywhere installer, then >> all of the sudden httpd starts responding >> 2) certain IE 11 client requests hang httpd 2.4. >> >> I've wireshark'ed #2 and at some point, an http GET gets an ACK and >> nothing more. I've peeked a little bit at the process threads with >> processexplorer (unfortunately i'm not a windows developer, so I'm not >> entirely familiar with the low level windows stuff) and everyhting >> looks >> like it's okay and simply waiting for requests. >> >> What I found after googling and testing is AcceptFilter http|https >> none >> prevents both of those problems. I've not yet tried connect to see if >> that works either. >> >> But what I'm really wondering about is, can anyone explain, especially >> in #2, what it is about AcceptFilter http none that actually resolves >> these types of issues? >> >> Thanks, >> Andy >> >> >> >> >> >>
