我们最近升级到Play 2.7.0并使用play2-reactivemongo版本0.16.2和reactivemongo 0.16.3。我们使用reactivemongo-shaded-native但也试过没有。
我们正在连接到具有3个节点的副本集，MongoDB Atlas上的MongoDB 3.6.10。
初始连接很好，服务运行一段时间。
但最终我们遇到了这个错误：
[error] 2019-02-15 09:40:30,466 r.api.Failover2 - [Supervisor-1/Connection-2] Got an error, no more attempts to do. Completing with a failure...
reactivemongo.core.actors.Exceptions$PrimaryUnavailableException: MongoError['No primary node is available! (Supervisor-1/Connection-2)']
Caused by: reactivemongo.core.actors.Exceptions$InternalState: null
at reactivemongo.ConnectAll$IsMaster(400, {{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Unknown (20/20 available connections), latency=9223372036854775807, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=135, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=140, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223615628>)
at reactivemongo.IsMaster(400, {{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Unknown (20/20 available connections), latency=9223372036854775807, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=135, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=21, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223615626>)
at reactivemongo.ConnectAll$IsMaster(399, {{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Unknown (20/20 available connections), latency=9223372036854775807, authenticated={}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=135, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=21, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223615623>)
at reactivemongo.IsMaster(399, {{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Unknown (20/20 available connections), latency=9223372036854775807, authenticated={}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=17, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=21, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223615622>)
at reactivemongo.RefreshAll({{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Primary (20/20 available connections), latency=30591, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=17, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=21, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223615486>)
at reactivemongo.PrimaryUnavailable(<time:1550223615485>)
at reactivemongo.ConnectAll({{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Primary (20/20 available connections), latency=30591, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=17, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=21, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223615475>)
at reactivemongo.ConnectAll$IsMaster(397, {{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Primary (20/20 available connections), latency=30591, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=17, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=21, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223605498>)
at reactivemongo.IsMaster(397, {{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Primary (20/20 available connections), latency=30591, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=17, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=15, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223605498>)
at reactivemongo.ConnectAll$IsMaster(396, {{NodeSet Some(PlayappDevelopment-shard-0) Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: Primary (20/20 available connections), latency=30591, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-01-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=17, authenticated={Authenticated(admin,playapp_rw)}] | Node[playappdevelopment-shard-00-02-tedsb.mongodb.net:27017: Secondary (20/20 available connections), latency=15, authenticated={Authenticated(admin,playapp_rw)}] }})(<time:1550223605493>)
还有这个：
[error] 2019-02-15 09:40:25,157 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] Oups. 80193 not found! complete message is Response(MessageHeader(16775938,220053,80193,1), Reply(8,0,0,1), ResponseInfo(b0706d7f))
[error] 2019-02-15 09:40:25,720 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] Oups. 79580 not found! complete message is Response(MessageHeader(16776408,220065,79580,1), Reply(8,0,0,1), ResponseInfo(5c65523c))
[error] 2019-02-15 09:40:26,616 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] Oups. 80346 not found! complete message is Response(MessageHeader(16776173,220060,80346,1), Reply(8,0,0,1), ResponseInfo(5613ea02))
[error] 2019-02-15 09:40:26,702 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] Oups. 80457 not found! complete message is Response(MessageHeader(16776643,220079,80457,1), Reply(8,0,0,1), ResponseInfo(2fa23bb9))
[error] 2019-02-15 09:40:29,612 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] Oups. 80174 not found! complete message is Response(MessageHeader(16776878,220102,80174,1), Reply(8,0,0,1), ResponseInfo(4faa6eec))
[error] 2019-02-15 09:40:30,257 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] Oups. 80191 not found! complete message is Response(MessageHeader(16776643,220111,80191,1), Reply(8,0,0,1), ResponseInfo(1fb6b5e0))
似乎应用程序无法完全恢复 - 20个请求中的1个成功。
2019-02-15 09:59:45,476 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] Node[playappdevelopment-shard-00-00-tedsb.mongodb.net:27017: \
Unknown (20/20 available connections), latency=9223372036854775807, authenticated={Authenticated(admin,playapp_rw)}] \
hasn't answered in time to last ping! Please check its connectivity
有一大堆“No channel for request”消息：
2019-03-05 15:02:58,433 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48879, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:58,580 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48880, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:58,678 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48881, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:58,777 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48882, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:58,874 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48883, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:58,972 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48884, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:59,069 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48885, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:59,220 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48886, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:59,318 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48887, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:59,416 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48888, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:59,514 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48889, 0, Query(0,assets.$cmd,0,1), Primary, None)
2019-03-05 15:02:59,611 r.c.a.MongoDBSystem - [Supervisor-1/Connection-2] No channel for request: Request(48890, 0, Query(0,assets.$cmd,0,1), Primary, None)
这似乎与Play HTTP服务器的大量并发请求有关，这可能会使主节点的所有可用通道饱和，从而导致主状态的任何刷新失败。
显然，当连接到只有一个节点的本地副本集时，我们没有这个问题。
问题是，我该如何解决这个问题？
任何人都可以理解提供的日志消息吗？
我的分析是否正确，即。是否会发生ReactiveMongo无法查询主要状态，因为频道只是“忙”？
更新：我们从ReactiveMongo（在过去的4年中为我们提供了很好的服务）转换为官方的mongo-scala驱动程序 - 这真的很痛苦，而且仍然是（主要是因为“注册表” - 无编译时间-type-safety概念传递Class[T]s，等等）但我们不再看到连接问题。
将Reactive Mongo升级到0.17.1后，它适用于我们
您似乎达到了可用连接的限制：您是否尝试过调整连接参数http://reactivemongo.org/releases/0.11/documentation/tutorial/connect-database.html？ Atlas通常支持20多个连接https://docs.atlas.mongodb.com/connection-limits/
我用mongo本地scala驱动程序解决了类似的问题，设置了50个连接池，更长的等待队列和更长的等待时间（与Atlas相关的延迟）
你试过吗：http://reactivemongo.org/releases/0.1x/documentation/tutorial/connect-database.html#netty-native
有一个类似的错误和一位同事建议如上。似乎为我们工作。