dynamic URIs and overlapping method requests on URIs
by David Robinson
I believe these two questions are very basic based on the posts I've read
so far on the mailing list. I appreciate your insights into how to handle
these correctly using undertow handlers (was thinking custom handlers).
First topic: a portion of the URI for my app is "dynamic" and changes as my
program runs.
For example, with this URI:
/xd/cohort1/healthevents/examdata
the "cohort1" portion "appears" after my program starts.
Each cohort may have distinct processing - so this URI:
/xd/cohort0/healthevents/examdata
needs to be handled by code that may be entirely different from the first
URI.
In a first approach, a single custom handler for the path /sd/* was
configured:
rh0 = new RoutingHandler().post("/xd/*", new
UndertowEventHttpHandler(config, posthandlers));
Undertow server = Undertow.builder().addHttpListener(ipPort,
ipAddress).setHandler(rh0).build();
That examined the URI, validated the "cohort" piece, and then called a
separate helper class directly (no dispatch, or async) to process the
request.
Is this the best approach or is there a better way to handle this with
Undertow?
(The out-of-the-box Path Template handler, for example, did not seem
dynamic enough to handle this sort of URI.)
Second topic: the application can receive "GETS" and "POSTS" to the same
URI.
A "GET" to /xd/cohort1/healthevents/examdata would return data where a
POST to /xd/cohort1/healthevents/examdata would expect the body of the
message to have JSON to be stored.
How to best handle both GET and POST messages coming to the same URI with
Undertow? I started to add an extra layer of abstraction - a generic
handler that looked at the request method
HttpString hString = exchange.getRequestMethod();
but was not sure where to go from there...do I then call the specialized
POST and GET handlers with .dispatch (deprecated except if I provide an
Executor?) or is there a way to register two handlers for the same
path...just different request methods?
Thank you,
6 months
Re: [undertow-dev] Too many open files: Exception accepting request, closing server channel TCP server (NIO)
by Nishant Kumar
I agree that it's a load-balancing issue but we can't do much about it at
this moment.
I still see issues after using the latest XNIO (3.7.7) with Undertow. what
I have observed it that when there is a spike in request
and CONNECTION_HIGH_WATER is reached, the server stops accepting new
connection as expected and the client starts to close the connection
because of delay (we have strict low latency requirement < 100ms) and try
to create new connection again (which will also not be accepted) but server
has not closed those connections (NO_REQUEST_TIMEOUT = 6000) and there will
be high number of CLOSE_WAIT connections at this moment. The server is
considering CLOSE_WAIT + ESTABLISHED for CONNECTION_HIGH_WATER (my
understanding).
Is there a way that I can close all CLOSE_WAIT connection at this moment
so that connection counts drop under CONNECTION_HIGH_WATER and we start
responding to newly established connections? or any other suggestions? I
have tried removing CONNECTION_HIGH_WATER and relying on the FD limit but
that didn't work.
On Sun, Mar 1, 2020 at 7:47 AM Stan Rosenberg <stan.rosenberg(a)gmail.com>
wrote:
> On Sat, Feb 29, 2020 at 8:18 PM Nishant Kumar <nishantkumar35(a)gmail.com>
> wrote:
>
>> Thanks for the reply. I am running it under supervisord and i have
>> updated open file limit in supervisord config. The problem seems to be same
>> as what @Carter has mentioned. It happens mostly during sudden traffic
>> spike and then sudden increase (~30k-300k) of TIME_WAIT socket.
>>
>
> The changes in
> https://github.com/xnio/xnio/pull/206/files#diff-23a6a7997705ea72e4016c11... are
> likely to improve the exceptional case of exceeding the file descriptor
> limit. However, if you're already setting the limit too high (e.g., in our
> case it was 795588), then exceeding it is a symptom of not properly
> load-balancing your traffic; with that many connections, you'd better have
> a ton of free RAM available.
>
--
Nishant Kumar
Bangalore, India
Mob: +91 80088 42030
Email: nishantkumar35(a)gmail.com
6 months, 1 week
Proxy and chunking.
by Jocke Eriksson
Hi devs and followers we have a problem and maybe someone on this list have some input.
We use undertow as an API gateway in front of JBoss application servers.
One API we have is responding with a chunked response, and the receiving side is expecting that each chunk is a valid JSon object.
When we analyze the TCP dumps it looks like some chunks are not the full JSon response we are expecting.
So the question is could this be a problem in the gateway?
I found a flag called PRE_CHUNKED_RESPONSE could this be the answer.
If so, how do we apply it in a proxy handler?
Regards Joakim.
6 months, 2 weeks
Worker queue timeout
by James Howe
Under load, when the worker threads are saturated, new requests will be queued.
Is there a way to timeout these requests, so that it doesn't waste time serving them later when the client has already given up?
I saw a reference to RequestLimitingHandler having a configurable timeout, but that doesn't appear to be true.
I also don't want any limit to how many request that can be waiting, only how long they can wait.
This doesn't seem to be a feature offered by any of the standard Java ExecutorService implementations,
but perhaps Undertow has added this (or an appropriate extension point for this) somewhere?
Thanks
James
6 months, 3 weeks
Too many open files: Exception accepting request, closing server channel TCP server (NIO)
by Nishant Kumar
Hi,
I am using undertow-core (2.0.29.Final) with Java 11. Every once in a while
(1-2 days) I got Too many open files error on my high load server (30k
JSON Request/sec) and then it stops responding. I have noticed that it
happens during full GC (but not during all full GC). Could you please help
me to fix this? I have also noticed that Undertow is using a very old
version of XNIO (3.3.8.Final). Any particular reason for that?
*System info:*
*RAM:* 64 GB
*Core:* 24 with hyperthreading (2 Thread per core)
*Java version: *11
*VM option: *-server -Xms12g -Xmx16g -verbose:gc
-Xloggc:/home/platform/platform-java/logs/platform-gc.log
-Dorg.wildfly.openssl.path=/usr/local/ssl/lib
-Dlog4j.configurationFile=/home/platform/platform-java/src/main/resources/log4j2.xml
*$] netstat -nalp | grep java | grep -E ":80 |:443 " | awk '{print $6}'|
sort | uniq -c*
7916 ESTABLISHED
2 LISTEN
*$] ulimit -a*
core file size (blocks, -c) 0
data seg size (kbytes, -d) unlimited
scheduling priority (-e) 0
file size (blocks, -f) unlimited
pending signals (-i) 256172
max locked memory (kbytes, -l) 64
max memory size (kbytes, -m) unlimited
open files (-n) 800000
pipe size (512 bytes, -p) 8
POSIX message queues (bytes, -q) 819200
real-time priority (-r) 0
stack size (kbytes, -s) 15360
cpu time (seconds, -t) unlimited
max user processes (-u) 65535
virtual memory (kbytes, -v) unlimited
file locks (-x) unlimited
*$] openssl version*
OpenSSL 1.1.1d 10 Sep 2019
*$] cat /etc/redhat-release*
CentOS Linux release 7.6.1810 (Core)
*$] uname -a*
Linux web2.ams.bidstalk.com 5.1.6-1.el7.elrepo.x86_64 #1 SMP Fri May 31
11:04:58 EDT 2019 x86_64 x86_64 x86_64 GNU/Linux
*Undertow code:*
server = Undertow.builder()
.addHttpListener(80, "0.0.0.0")
.addHttpsListener(443, "0.0.0.0", sslContext)
.setWorkerThreads(32)
.setServerOption(UndertowOptions.ENABLE_HTTP2, true)
.setServerOption(UndertowOptions.IDLE_TIMEOUT, 120000) // 12000ms
.setServerOption(org.xnio.Options.SSL_SERVER_SESSION_CACHE_SIZE,
1024 * 20) // 20000 sessions
.setServerOption(org.xnio.Options.SSL_SERVER_SESSION_TIMEOUT,
3000) // 5m
.setIoThreads(20)
.setWorkerOption(org.xnio.Options.TCP_NODELAY, true)
.setSocketOption(org.xnio.Options.TCP_NODELAY, true)
.setSocketOption(org.xnio.Options.KEEP_ALIVE, true)
.setSocketOption(org.xnio.Options.REUSE_ADDRESSES, true)
.setSocketOption(org.xnio.Options.CONNECTION_HIGH_WATER, 20000)
.setSocketOption(org.xnio.Options.CONNECTION_LOW_WATER, 20000)
.setWorkerOption(org.xnio.Options.THREAD_AFFINITY, false)
.setHandler(Handlers.routing().post("/", new
RequestHandler(appContext)))
.build();
server.start();
*error.log*
2020-02-28 23:19:05.997 [ERROR] [XNIO-1 Accept]
org.xnio.nio.QueuedNioTcpServerHandle:handleReady(-1): Exception
accepting request, closing server channel TCP server (NIO) <910f2428>
java.io.IOException: Too many open files
at sun.nio.ch.ServerSocketChannelImpl.accept0(Native Method) ~[?:?]
at sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:533)
~[?:?]
at sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:285)
~[?:?]
at org.xnio.nio.QueuedNioTcpServer.handleReady(QueuedNioTcpServer.java:467)
[xnio-nio-3.3.8.Final.jar:3.3.8.Final]
at org.xnio.nio.QueuedNioTcpServerHandle.handleReady(QueuedNioTcpServerHandle.java:38)
[xnio-nio-3.3.8.Final.jar:3.3.8.Final]
at org.xnio.nio.WorkerThread.run(WorkerThread.java:561)
[xnio-nio-3.3.8.Final.jar:3.3.8.Final]
2020-02-28 23:19:06.201 [ERROR] [XNIO-1 Accept]
org.xnio.nio.QueuedNioTcpServerHandle:handleReady(-1): Exception
accepting request, closing server channel TCP server (NIO) <9834817a>
java.io.IOException: Too many open files
at sun.nio.ch.ServerSocketChannelImpl.accept0(Native Method) ~[?:?]
at sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:533)
~[?:?]
at sun.nio.ch.ServerSocketChannelImpl.accept(ServerSocketChannelImpl.java:285)
~[?:?]
at org.xnio.nio.QueuedNioTcpServer.handleReady(QueuedNioTcpServer.java:467)
[xnio-nio-3.3.8.Final.jar:3.3.8.Final]
at org.xnio.nio.QueuedNioTcpServerHandle.handleReady(QueuedNioTcpServerHandle.java:38)
[xnio-nio-3.3.8.Final.jar:3.3.8.Final]
at org.xnio.nio.WorkerThread.run(WorkerThread.java:561)
[xnio-nio-3.3.8.Final.jar:3.3.8.Final]*/var/log/messages :*
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:47 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: net_ratelimit: 21918 callbacks suppressed
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:52 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:57 web2 kernel: net_ratelimit: 60720 callbacks suppressed
Feb 28 23:18:57 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:57 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
Feb 28 23:18:57 web2 kernel: nf_conntrack: nf_conntrack: table full,
dropping packet
..
..
--
Nishant Kumar
Bangalore, India
Mob: +91 80088 42030
Email: nishantkumar35(a)gmail.com
6 months, 3 weeks
