Avoid concurrent read and writes to dcp opcode counters

2018-07-12T17:05:59.106-07:00, ns_log:0:info:message(ns_1@172.23.96.56) - Service 'eventing' exited with status 134. Restarting. Messages:

runtime.gopark(0xe45b40, 0x0, 0xd8ed73, 0x6, 0x18, 0x2)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/runtime/proc.go:259 +0x13a fp=0xc42136aba8 sp=0xc42136ab78

runtime.selectgoImpl(0xc42136af18, 0x0, 0x18)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/runtime/select.go:423 +0x1235 fp=0xc42136ae08 sp=0xc42136aba8

runtime.selectgo(0xc42136af18)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/runtime/select.go:238 +0x1c fp=0xc42136ae30 sp=0xc42136ae08

github.com/couchbase/eventing/consumer.(*Consumer).updateWorkerStats(0xc421f06a00)

	goproj/src/github.com/couchbase/eventing/consumer/stats_updater.go:136 +0x4c2 fp=0xc42136afa8 sp=0xc42136ae30

runtime.goexit()

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/runtime/asm_amd64.s:2086 +0x1 fp=0xc42136afb0 sp=0xc42136afa8

created by github.com/couchbase/eventing/consumer.(*Consumer).Serve

	goproj/src/github.com/couchbase/eventing/consumer/v8_consumer.go:313 +0x1b9d

[goport(/opt/couchbase/bin/eventing-producer)] 2018/07/12 17:05:59 child process exited with status 134

2018-07-12T17:05:59.118-07:00, ns_orchestrator:0:critical:message(ns_1@172.23.108.103) - Rebalance exited with reason {service_rebalance_failed,eventing,

                                 {lost_connection,shutdown}}

fatal error: concurrent map read and map write

2018-07-12T17:05:58.632-07:00 [Info] client::Serve [worker_bucket_op_function_2:/tmp/127.0.0.1:8091_worker_bucket_op_function_2.sock:26746] Informing Eventing.Producer to stop Eventing.Consumer instance: consumer => app: bucket_op_function name: worker_bucket_op_function_2 tcpPort: /tmp/127.0.0.1:8091_worker_bucket_op_function_2.sock ospid: 26746 dcpEventProcessed: DCP_STREAMREQ:1762 DCP_STREAMEND:2049 DCP_SNAPSHOT:15394 DCP_MUTATION:297970 DCP_DELETION:924831 v8EventProcessed: THR_MAP:1 HANDLER_CODE:1 FAILURE_STATS:3760 LATENCY_STATS:3760 EXECUTION_STATS:3760 LCB_EXCEPTION_STATS:3760 LOG_LEVEL:1 THR_COUNT:1 V8_INIT:1 V8_LOAD:1 SOURCE_MAP:1

goroutine 1499702 [running]:

runtime.throw(0xda598e, 0x21)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/runtime/panic.go:566 +0x95 fp=0xc430c65058 sp=0xc430c65038

runtime.mapaccess2(0xc71a80, 0xc42f9be900, 0xc430c650db, 0x15bf560, 0x4f1a00)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/runtime/hashmap.go:340 +0x249 fp=0xc430c650a0 sp=0xc430c65058

github.com/couchbase/eventing/util.SprintDCPCounts(0xc42f9be900, 0xc4455ca000, 0xa5, 0xc430c651b0, 0x4113ff, 0x15a5c20, 0x7fb14bcfa278)

	goproj/src/github.com/couchbase/eventing/util/util.go:139 +0xb7 fp=0xc430c65160 sp=0xc430c650a0

github.com/couchbase/eventing/consumer.(*Consumer).String(0xc42b623400, 0xe415c8, 0xc4410b9800)

	goproj/src/github.com/couchbase/eventing/consumer/v8_consumer.go:551 +0x47 fp=0xc430c65250 sp=0xc430c65160

fmt.(*pp).handleMethods(0xc4410b9800, 0x76, 0x644526c901)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/fmt/print.go:590 +0x2f6 fp=0xc430c65300 sp=0xc430c65250

fmt.(*pp).printArg(0xc4410b9800, 0xd83420, 0xc42b623400, 0x76)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/fmt/print.go:665 +0x17b fp=0xc430c653f8 sp=0xc430c65300

fmt.(*pp).doPrintf(0xc4410b9800, 0xc432730880, 0x7f, 0xc430c65880, 0x6, 0x6)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/fmt/print.go:985 +0x123d fp=0xc430c654e0 sp=0xc430c653f8

fmt.Sprintf(0xc432730880, 0x7f, 0xc430c65880, 0x6, 0x6, 0xc432730880, 0x7f)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/fmt/print.go:196 +0x6a fp=0xc430c65538 sp=0xc430c654e0

log.(*Logger).Printf(0xc42012e140, 0xc432730880, 0x7f, 0xc430c65880, 0x6, 0x6)

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/log/log.go:173 +0x53 fp=0xc430c65580 sp=0xc430c65538

github.com/couchbase/eventing/logging.printf(0x4, 0xdbcf21, 0x5a, 0xc430c65880, 0x6, 0x6)

	goproj/src/github.com/couchbase/eventing/logging/logging.go:116 +0x27e fp=0xc430c65618 sp=0xc430c65580

github.com/couchbase/eventing/logging.Infof(0xdbcf21, 0x5a, 0xc430c65880, 0x6, 0x6)

	goproj/src/github.com/couchbase/eventing/logging/logging.go:133 +0x5c fp=0xc430c65658 sp=0xc430c65618

github.com/couchbase/eventing/producer.(*Producer).KillAndRespawnEventingConsumer(0xc42b75e700, 0x157a840, 0xc42b623400)

	goproj/src/github.com/couchbase/eventing/producer/producer.go:621 +0x596 fp=0xc430c658f0 sp=0xc430c65658

github.com/couchbase/eventing/consumer.(*client).Serve(0xc43a4d0770)

	goproj/src/github.com/couchbase/eventing/consumer/client.go:143 +0x1474 fp=0xc430c65f50 sp=0xc430c658f0

github.com/couchbase/eventing/suptree.(*Supervisor).runService.func1(0xc42b934e00, 0x0, 0x154a7a0, 0xc43a4d0770)

	goproj/src/github.com/couchbase/eventing/suptree/supervisor.go:398 +0x63 fp=0xc430c65f80 sp=0xc430c65f50

runtime.goexit()

	/home/couchbase/.cbdepscache/exploded/x86_64/go-1.7.6/go/src/runtime/asm_amd64.s:2086 +0x1 fp=0xc430c65f88 sp=0xc430c65f80

created by github.com/couchbase/eventing/suptree.(*Supervisor).runService

	goproj/src/github.com/couchbase/eventing/suptree/supervisor.go:401 +0x5b