问题
Encountered a strange problem, I couldn't reproduce it after some attempts. How to reproduce it and why it happend?
It's a non-concurrent task, Call the HTTP connection in a loop.
public static Response syncGet(URL url) throws IOException {
log.debug("http url:{}", url);
OkHttpClient client = new OkHttpClient().newBuilder().connectTimeout(15L, TimeUnit.SECONDS)
.readTimeout(30L, TimeUnit.SECONDS).build();
Request request = new Request.Builder().url(url).get().addHeader("cache-control", "no-cache").build();
Call call = client.newCall(request);
return call.execute();
}
stack:
2019-12-05 11:20:56.068 ERROR 18484 --- [ scheduling-1] o.s.s.s.TaskUtils$LoggingErrorHandler : Unexpected error occurred in scheduled task
java.lang.OutOfMemoryError: unable to create new native thread
at java.lang.Thread.start0(Native Method) [na:1.8.0_181]
at java.lang.Thread.start(Thread.java:717) [na:1.8.0_181]
at java.util.concurrent.ThreadPoolExecutor.addWorker(ThreadPoolExecutor.java:957) [na:1.8.0_181]
at java.util.concurrent.ThreadPoolExecutor.execute(ThreadPoolExecutor.java:1378) [na:1.8.0_181]
at okhttp3.ConnectionPool.put(ConnectionPool.java:153) ~[okhttp-3.12.1.jar:na]
at okhttp3.OkHttpClient$1.put(OkHttpClient.java:167) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.connection.StreamAllocation.findConnection(StreamAllocation.java:266) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.connection.StreamAllocation.findHealthyConnection(StreamAllocation.java:135) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.connection.StreamAllocation.newStream(StreamAllocation.java:114) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.connection.ConnectInterceptor.intercept(ConnectInterceptor.java:42) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.cache.CacheInterceptor.intercept(CacheInterceptor.java:93) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.BridgeInterceptor.intercept(BridgeInterceptor.java:93) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.RetryAndFollowUpInterceptor.intercept(RetryAndFollowUpInterceptor.java:126) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:147) ~[okhttp-3.12.1.jar:na]
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.java:121) ~[okhttp-3.12.1.jar:na]
at okhttp3.RealCall.getResponseWithInterceptorChain(RealCall.java:254) ~[okhttp-3.12.1.jar:na]
at okhttp3.RealCall.execute(RealCall.java:92) ~[okhttp-3.12.1.jar:na]
at chances.cms.util.HttpUtil.syncGet(HttpUtil.java:67) ~[classes/:na]
at chances.cms.task.CheckTask.checkContent(CheckTask.java:76) ~[classes/:na]
at chances.cms.task.CheckTask.check(CheckTask.java:60) ~[classes/:na]
at chances.cms.task.CheckTask.check(CheckTask.java:51) ~[classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_181]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_181]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_181]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_181]
at org.springframework.scheduling.support.ScheduledMethodRunnable.run(ScheduledMethodRunnable.java:84) ~[spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.scheduling.support.DelegatingErrorHandlingRunnable.run(DelegatingErrorHandlingRunnable.java:54) ~[spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.scheduling.concurrent.ReschedulingRunnable.run(ReschedulingRunnable.java:93) [spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511) [na:1.8.0_181]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) [na:1.8.0_181]
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$201(ScheduledThreadPoolExecutor.java:180) [na:1.8.0_181]
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:293) [na:1.8.0_181]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_181]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_181]
at java.lang.Thread.run(Thread.java:748) [na:1.8.0_181]
回答1:
OkHttpClients should be shared
OkHttp performs best when you create a single OkHttpClient instance and reuse it for all of your HTTP calls. This is because each client holds its own connection pool and thread pools. Reusing connections and threads reduces latency and saves memory.
more detail: https://square.github.io/okhttp/3.x/okhttp/okhttp3/OkHttpClient.html
so creating the client outside of the syncGet method should solve your problem.
来源：https://stackoverflow.com/questions/59189059/okhttp3-unable-to-create-new-native-thread