Di Ubuntu Server 10.04 saya, saya menjalankan contoh aplikasi node.js:
var http = require("http");
function onRequest(request, response) {
console.log("Request received.");
response.writeHead(200, {"Content-Type": "text/html"});
response.write("Hello World");
response.end();
}
http.createServer(onRequest).listen(3000);
Ini hanya mendengarkan permintaan pada port 3000, masuk konsol permintaan ini dan mengirim ke klien HTTP "Hello World"
Tujuannya adalah untuk membuat aplikasi ini hidup berdampingan dengan Apache2. Jadi setelah beberapa penelitian saya mengedit file default ( / etc / apache2 / sites-available / default ) dengan cara ini:
<VirtualHost *:80>
ServerAdmin haj@myserver.com
ServerName dev.myserver.com
<Location /node>
ProxyPassReverse http://127.0.0.1:3000/
ProxyPass http://127.0.0.1:3000/
</Location>
<Proxy>
Allow from all
</Proxy>
DocumentRoot /home/haj/www/http_home
<Directory />
Options FollowSymLinks
AllowOverride None
</Directory>
<Directory /home/haj/www/http_home/>
Options Indexes FollowSymLinks MultiViews
AllowOverride None
Order allow,deny
allow from all
</Directory>
ErrorLog /home/haj/www/log/error.log
# Possible values include: debug, info, notice, warn, error, crit,
# alert, emerg.
LogLevel warn
CustomLog /home/haj/www/log/access.log combined
</VirtualHost>
Jadi, ketika seorang pengguna melakukan panggilan ke http://dev.myserver.com/nodeatau http://dev.myserver.com/node/, Apache mem-proksi permintaan tersebut, Node.js melakukan pemrosesan, dan pengguna mendapatkan kembali "Hello World".
Hanya ada satu masalah: Butuh beberapa waktu untuk, Mari kita sebut 'Muat' Proksi, dengan kata lain, saya mendapatkan pesan-pesan ini di browser:
<503 Service Temporarily Unavailable>
Service Temporarily Unavailable
The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later.
Apache/2.2.14 (Ubuntu) Server at dev.neosource.cl Port 80
Selain itu, error.log memberi tahu saya:
[Thu Apr 21 01:02:10 2011] [error] proxy: HTTP: disabled connection for (127.0.0.1)
[Thu Apr 21 01:02:10 2011] [error] proxy: HTTP: disabled connection for (127.0.0.1)
[Thu Apr 21 01:02:10 2011] [error] proxy: HTTP: disabled connection for (127.0.0.1)
Lalu tiba-tiba, It Works, begitu saja. Tidak ada jumlah permintaan, tidak ada waktu, tidak ada pola sama sekali.
Dalam istilah awam, layanan harus 'memuat' , Itulah kesan yang diberikannya, tetapi, saya ingin tahu apakah ada cara untuk meminimalkan keterlambatan ini. Atau saya lebih suka tahu apa yang salah dengan konfigurasi yang disebutkan di atas.
Sunting 1 : Setelah memodifikasi LogLevel untuk debug, selama salah satu penundaan ini saya mendapatkan ini per permintaan:
[Thu Apr 21 02:30:40 2011] [debug] mod_proxy_http.c(56): proxy: HTTP: canonicalising URL //127.0.0.1:3000/
[Thu Apr 21 02:30:40 2011] [debug] proxy_util.c(1494): [client 200.xxx.yyy.zzz] proxy: http: found worker http://127.0.0.1:3000/ for http://127.0.0.1:3000/
[Thu Apr 21 02:30:40 2011] [debug] mod_proxy.c(993): Running scheme http handler (attempt 0)
[Thu Apr 21 02:30:40 2011] [debug] mod_proxy_http.c(1940): proxy: HTTP: serving URL http://127.0.0.1:3000/
[Thu Apr 21 02:30:40 2011] [debug] proxy_util.c(1937): proxy: HTTP: retrying the worker for (127.0.0.1)
[Thu Apr 21 02:30:40 2011] [error] proxy: HTTP: disabled connection for (127.0.0.1)
[Thu Apr 21 02:30:40 2011] [debug] mod_deflate.c(615): [client 200.xxx.yyy.zzz] Zlib: Compressed 405 to 273 : URL /node
... dan ketika itu benar lagi:
[Thu Apr 21 02:35:16 2011] [debug] mod_proxy_http.c(56): proxy: HTTP: canonicalising URL //127.0.0.1:3000/
[Thu Apr 21 02:35:16 2011] [debug] proxy_util.c(1494): [client 200.xxx.yyy.zzz] proxy: http: found worker http://127.0.0.1:3000/ for http://127.0.0.1:3000/
[Thu Apr 21 02:35:16 2011] [debug] mod_proxy.c(993): Running scheme http handler (attempt 0)
[Thu Apr 21 02:35:16 2011] [debug] mod_proxy_http.c(1940): proxy: HTTP: serving URL http://127.0.0.1:3000/
[Thu Apr 21 02:35:16 2011] [debug] proxy_util.c(1999): proxy: HTTP: has acquired connection for (127.0.0.1)
[Thu Apr 21 02:35:16 2011] [debug] proxy_util.c(2055): proxy: connecting http://127.0.0.1:3000/ to 127.0.0.1:3000
[Thu Apr 21 02:35:16 2011] [debug] proxy_util.c(2153): proxy: connected / to 127.0.0.1:3000
[Thu Apr 21 02:35:16 2011] [debug] proxy_util.c(2244): proxy: HTTP: backend socket is disconnected.
[Thu Apr 21 02:35:16 2011] [debug] proxy_util.c(2308): proxy: HTTP: fam 2 socket created to connect to 127.0.0.1
[Thu Apr 21 02:35:16 2011] [debug] proxy_util.c(2414): proxy: HTTP: connection complete to 127.0.0.1:3000 (127.0.0.1)
[Thu Apr 21 02:35:16 2011] [debug] mod_proxy_http.c(1723): proxy: start body send
[Thu Apr 21 02:35:16 2011] [debug] mod_deflate.c(615): [client 200.xxx.yyy.zzz] Zlib: Compressed 11 to 13 : URL /node
[Thu Apr 21 02:35:16 2011] [debug] mod_proxy_http.c(1816): proxy: end body send
[Thu Apr 21 02:35:16 2011] [debug] proxy_util.c(2017): proxy: HTTP: has released connection for (127.0.0.1)