- 问题spring-cloud-gateway 作为统一的请求入口，负责转发请求到相应的微服务中去。采用的 Spring Cloud 的版本为 Finchley SR2。测试一个接口的性能，发现 tps 只有 1000 req/s 左右就上不去了。[root@hystrix-dashboard wrk]# wrk -t 10 -c 200 -d 30s –latency -s post-test.lua ‘http://10.201.0.28:8888/api/v1/json’Running 30s test @ http://10.201.0.28:8888/api/v1/json 10 threads and 200 connections Thread Stats Avg Stdev Max +/- Stdev Latency 188.34ms 110.13ms 2.00s 78.43% Req/Sec 106.95 37.19 333.00 77.38% Latency Distribution 50% 165.43ms 75% 243.48ms 90% 319.47ms 99% 472.64ms 30717 requests in 30.04s, 7.00MB read Socket errors: connect 0, read 0, write 0, timeout 75Requests/sec: 1022.62Transfer/sec: 238.68KB其中 post-test.lua 内容如下：request = function() local headers = {} headers[“Content-Type”] = “application/json” local body = [[{ “biz_code”: “1109000001”, “channel”: “7”, “param”: { “custom_id”: “ABCD”, “type”: “test”, “animals”: [“cat”, “dog”, “lion”], “retcode”: “0” } }]] return wrk.format(‘POST’, nil, headers, body)end网关的逻辑是读取请求中 body 的值，根据 biz_code 字段去内存的路由表中匹配路由，然后转发请求到对应的微服务中去。2. 排查测试接口本身的性能：[root@hystrix-dashboard wrk]# wrk -t 10 -c 200 -d 30s –latency -s post-test.lua ‘http://10.201.0.32:8776/eeams-service/api/v1/json’Running 30s test @ http://10.201.0.32:8776/eeams-service/api/v1/json 10 threads and 200 connections Thread Stats Avg Stdev Max +/- Stdev Latency 26.72ms 8.59ms 260.23ms 89.66% Req/Sec 752.18 101.46 0.94k 78.67% Latency Distribution 50% 23.52ms 75% 28.02ms 90% 35.58ms 99% 58.25ms 224693 requests in 30.02s, 50.83MB readRequests/sec: 7483.88Transfer/sec: 1.69MB发现接口的 tps 可以达到 7000+。通过 spring-boot-admin 查看网关的 cpu、内存等占用情况，发现都没有用满；查看线程状况，发现 reactor-http-nio 线程组存在阻塞情况。对于响应式编程来说，reactor-http-nio 线程出现阻塞结果是灾难性的。通过 jstack 命令分析线程状态，定位阻塞的代码（第 19 行）：“reactor-http-nio-4” #19 daemon prio=5 os_prio=0 tid=0x00007fb784d7f240 nid=0x80b waiting for monitor entry [0x00007fb71befc000] java.lang.Thread.State: BLOCKED (on object monitor) at java.lang.ClassLoader.loadClass(ClassLoader.java:404) - waiting to lock <0x000000008b0cec30> (a java.lang.Object) at org.springframework.boot.loader.LaunchedURLClassLoader.loadClass(LaunchedURLClassLoader.java:93) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) at org.springframework.util.ClassUtils.forName(ClassUtils.java:282) at org.springframework.http.converter.json.Jackson2ObjectMapperBuilder.registerWellKnownModulesIfAvailable(Jackson2ObjectMapperBuilder.java:753) at org.springframework.http.converter.json.Jackson2ObjectMapperBuilder.configure(Jackson2ObjectMapperBuilder.java:624) at org.springframework.http.converter.json.Jackson2ObjectMapperBuilder.build(Jackson2ObjectMapperBuilder.java:608) at org.springframework.http.codec.json.Jackson2JsonEncoder.<init>(Jackson2JsonEncoder.java:54) at org.springframework.http.codec.support.AbstractCodecConfigurer$AbstractDefaultCodecs.getJackson2JsonEncoder(AbstractCodecConfigurer.java:177) at org.springframework.http.codec.support.DefaultServerCodecConfigurer$ServerDefaultCodecsImpl.getSseEncoder(DefaultServerCodecConfigurer.java:99) at org.springframework.http.codec.support.DefaultServerCodecConfigurer$ServerDefaultCodecsImpl.getObjectWriters(DefaultServerCodecConfigurer.java:90) at org.springframework.http.codec.support.AbstractCodecConfigurer.getWriters(AbstractCodecConfigurer.java:121) at org.springframework.http.codec.support.DefaultServerCodecConfigurer.getWriters(DefaultServerCodecConfigurer.java:39) at org.springframework.web.reactive.function.server.DefaultHandlerStrategiesBuilder.build(DefaultHandlerStrategiesBuilder.java:103) at org.springframework.web.reactive.function.server.HandlerStrategies.withDefaults(HandlerStrategies.java:90) at org.springframework.cloud.gateway.support.DefaultServerRequest.<init>(DefaultServerRequest.java:81) at com.glsc.imf.dbg.route.RouteForJsonFilter.filter(RouteForJsonFilter.java:34) at org.springframework.cloud.gateway.handler.FilteringWebHandler$DefaultGatewayFilterChain.lambda$filter$0(FilteringWebHandler.java:115) at org.springframework.cloud.gateway.handler.FilteringWebHandler$DefaultGatewayFilterChain$$Lambda$800/1871561393.get(Unknown Source) at reactor.core.publisher.MonoDefer.subscribe(MonoDefer.java:44)最终定位到问题代码为：DefaultServerRequest req = new DefaultServerRequest(exchange); // 这行代码存在性能问题return req.bodyToMono(JSONObject.class).flatMap(body -> { …});这里的逻辑是我需要读取请求中 body 的值，并转化为 json，之后根据其中的特定字段去匹配路由，然后进行转发。这里选择了先把 exchange 转化为 DefaultServerRequest，目的是为了使用该类的 bodyToMono 方法，可以方便的进行转换。3. 解决改写代码以实现同样的功能：return exchange.getRequest().getBody().collectList() .map(dataBuffers -> { ByteBuf byteBuf = Unpooled.buffer(); dataBuffers.forEach(buffer -> { try { byteBuf.writeBytes(IOUtils.toByteArray(buffer.asInputStream())); } catch (IOException e) { e.printStackTrace(); } }); return JSON.parseObject(new String(byteBuf.array())); }) .flatMap(body -> { … });之后进行测试，[root@hystrix-dashboard wrk]# wrk -t 10 -c 200 -d 30s –latency -s post-test.lua ‘http://10.201.0.28:8888/api/v1/json’Running 30s test @ http://10.201.0.28:8888/api/v1/json 10 threads and 200 connections Thread Stats Avg Stdev Max +/- Stdev Latency 48.47ms 45.85ms 325.87ms 88.55% Req/Sec 548.13 202.55 760.00 80.01% Latency Distribution 50% 31.18ms 75% 39.44ms 90% 112.18ms 99% 227.19ms 157593 requests in 30.02s, 35.94MB readRequests/sec: 5249.27Transfer/sec: 1.20MB发现 tps 从 1000 提升到了 5000+，问题解决。