部署方式：docker-compose
nebula graph版本号：v2-nightly
importer版本号：v2
配置文件：
各位大佬能帮忙看看是啥问题吗，前面一直导得好好的，后面就报这个错，刚开始以为是连接池里的连接没有释放的原因，就把concurrency设为1，还是报这个错。
2021/06/03 04:46:28 [INFO] statsmgr.go:61: Tick: Time(8315.00s), Finished(41857928), Failed(0), Latency AVG(4329us), Batches Req AVG(6327us), Rows AVG(5034.03/s)
2021/06/03 04:46:29 [ERROR] session.go:41: [nebula-clients] Failed to reconnect, Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
2021/06/03 04:46:30 [ERROR] session.go:41: [nebula-clients] Failed to reconnect, Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
2021/06/03 04:46:31 [ERROR] session.go:41: [nebula-clients] Failed to reconnect, Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
2021/06/03 04:46:32 [ERROR] handler.go:63: Client 0 fail to execute: INSERT EDGE `contact`() VALUES "aca77bda8e35b8a42413d7d3edcdf5e0"->"0bfa7f529d8d6b2384908fcbec6ed670":() , "0f838509cd781997ac1ea52b1f3d70ab"->"e4b0972c86091e1514d64ee904041cc7":() , "1831ea8f979ae73221448f701c19c8b3"->"7ebab446ccec7f75d458f8e886c6b207":() , "520b55dfaed482c8354f52306f1c2cf8"->"7ce5c4f44a44e25318f38c9a992b9718":() , "ac4986df21db870247a4d7128bc0870d"->"fbcae62712bfe3c7b1c3aaa137db60a6":() , "67853611868d28a51ff795d516321c97"->"c6aaf267a8a0844d8ddaf61e8ce7a896":() , "3a593f584913de0cd647e8aede201bea"->"53b59ed633df0a782573c37153b1dfbd":() , "d51ba187a0ea8dd8fb41c0c755a59c3f"->"4c35829763be69a44ff830e616d53db9":() , "16317b1bd08b63d80fade55cba72048f"->"694a1d98f1c5bbf67c3611f261ece2f9":() , "00886b8f8ec349f5879b9a0629b5b98d"->"4114ca2ee27b41eb51208edc4080bb78":() , "1d887527f3eceed03c49c5b5e20cd867"->"bc1a5d68b9eefb58f1d664dab9384534":() , "b67ae4f5025a4017a4a883199064b7be"->"07642e1cf0a4c50c0045ab6e5f509515":() , "f303bd7db4d72b9774fce936ec5260f6"->"ab5c9bee85a46b289688a0c4b62cc4f6":() , "6ac8cff6b95b0d5def59fdcc4f0e83c2"->"13b50c54cfdbe88a139c225eced1335d":() , "de1dcabf9976c4d9263bb4f6a8d74a32"->"122641a7fea0d587458aeaa57eeb260e":() , "5b8f844488c2a75c98dc019fbbd634b4"->"7617a96a1b08dcecbfa97eaaadbcb3cb":() , "b5f697d3abcfce293eb1e216a0678251"->"a4bb278be9d1f096e670a3d3344271c7":() , "9033f9b602c6dbb6d42673f77f043488"->"5cfede6d2d2b1a4979a295e94cc708b0":() , "83302c09482fee8dcc9f365b068b99a4"->"f560aef0b9d5f6ea2562c13b89d0bd54":() , "d33530879ceea8cf2d18e26bdd2e7405"->"b13e732f2da19a0925fa137e29ff1546":() , "7ee5b9acb75101f09ab65a7b7005467c"->"f156003ca7da1e7e52504de0ca36efb3":() , "f34e53cd636c2477f3a06ba5719bb020"->"88aaa533b2128912bda698d3d6a372ce":() , "a00fb15b7fc1f2414e3bdffbba3e6258"->"a148b974f137b4dd06756f3ecb5160dd":() , "99026c44bfd34454b5b37485e91c9c11"->"53471a11d6631294962ffe706dd2f3c6":() , "96a3f45d796b2bf801187e8a26e042cb"->"acbaf59cb986b0e5e7c0af74d22e8a10":() , "82f2fe8ce48f39afe926196f974b0eac"->"67972147a84d5e098b5367155c5f2538":() , "f3dec0d048723f6a7c861bea8289e71d"->"7ce0cc2c120c047c55496510c0e1741b":() , "245219508ce86738dbbacb04d15710e7"->"6639a46f1b6e36e1f16fbbf18498cc44":() , "e66fc7d7c5fa6f19c3002d2165820b48"->"b15e86b1f9f35a4abc492385465e0455":() , "c276112b10aa1ba610b6c89d7c92ffc4"->"fc81596f4842489387a0968b7ba82ba6":() , "71a62df626daffa82672ab9cd311edee"->"b0fbb25b61702009152429f07d9d393e":() , "0b8e28a1f24ba617e175b52c5ac3ddf5"->"d086be8f026c6674becd4097486a66fe":() ;, Error: Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
2021/06/03 04:46:32 [ERROR] session.go:41: [nebula-clients] Failed to reconnect, Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
2021/06/03 04:46:33 [INFO] statsmgr.go:61: Tick: Time(8320.00s), Finished(41864392), Failed(32), Latency AVG(4329us), Batches Req AVG(6327us), Rows AVG(5031.78/s)
2021/06/03 04:46:33 [ERROR] session.go:41: [nebula-clients] Failed to reconnect, Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
2021/06/03 04:46:34 [ERROR] session.go:41: [nebula-clients] Failed to reconnect, Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
2021/06/03 04:46:35 [ERROR] session.go:41: [nebula-clients] Failed to reconnect, Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
2021/06/03 04:49:33 [ERROR] session.go:41: [nebula-clients] Failed to reconnect, Failed to get connection: No valid connection in the idle queue and connection number has reached the pool capacity
panic: runtime error: invalid memory address or nil pointer dereference
[signal SIGSEGV: segmentation violation code=0x1 addr=0x20 pc=0x713c06]
goroutine 22 [running]:
github.com/vesoft-inc/nebula-go.(*Session).Execute(0xc00009dce0, 0xc0003fe700, 0x60a, 0x0, 0x8652c0, 0xc00024ba00)
/go/pkg/mod/github.com/vesoft-inc/nebula-go@v1.1.1-0.20210128173938-f922255c1fbd/session.go:53 +0x406
github.com/vesoft-inc/nebula-importer/pkg/client.(*ClientPool).startWorker(0xc000129e30, 0x0)
/home/nebula-importer/pkg/client/clientpool.go:167 +0x1bd
github.com/vesoft-inc/nebula-importer/pkg/client.(*ClientPool).Init.func1(0xc000129e30, 0x0)
/home/nebula-importer/pkg/client/clientpool.go:139 +0x3e
created by github.com/vesoft-inc/nebula-importer/pkg/client.(*ClientPool).Init
/home/nebula-importer/pkg/client/clientpool.go:134 +0x60