Add tags cache to app.proxyman.ohm.Select()

[vrnobody]

负载均衡从outbounds manager获取tags时，很多时候返回的tags是相同的。这个PR给ohm.Select()添加缓存，减少sort次数。

[yuhan6665]

根据之前的讨论 outbound tags 会变 所以这个 cache 应该不行
#2898 (comment)

[vrnobody]

这里tagsCache的key是selectors他是源于config.json的routing.balancers.selector数组。用在上面那个issue里面就是["proxy"]。这个值通常不怎么变。然后ohm.Select()这个函数是根据上面这个值从taggedOutbounds里面匹配tag的前缀，所以taggedOutbounds不变的情况下，返回的tags也是相同的，只是golang的map是无序的，导致tags里面的值的顺序会发生变化，但是sort之后就不变了。

然后是issue里面讨论的通过api增删outbounds的情况。这个PR在ohm.AddHandler()和ohm.RemoveHandler()里面都加了m.tagsCache = make(map[string][]string)对cache重置，这时会重新挑选outbound tags存入cache。

用issue讨论的情况实测结果

Xray 1.8.7 (Xray, Penetrates Everything.) Custom (go1.21.6 windows/amd64)
A unified platform for anti-censorship.
2024/01/12 08:55:29 [Info] infra/conf/serial: Reading config: stdin:
2024/01/12 08:55:29 [Warning] core: Xray 1.8.7 started
2024/01/12 08:55:36 127.0.0.1:8290 accepted //browser.events.data.msn.cn:443 [http -> proxyA]
2024/01/12 08:55:36 127.0.0.1:8291 accepted //ntp.msn.cn:443 [http -> proxyB]
2024/01/12 08:55:37 127.0.0.1:8296 accepted //assets.msn.cn:443 [http -> proxyC]
2024/01/12 08:55:37 127.0.0.1:8298 accepted //edgeservices.bing.com:443 [http -> proxyA]
2024/01/12 08:55:37 127.0.0.1:8299 accepted //assets.msn.cn:443 [http -> proxyB]
2024/01/12 08:55:37 127.0.0.1:8302 accepted //browser.events.data.msn.cn:443 [http -> proxyC]
2024/01/12 08:55:37 127.0.0.1:8304 accepted //img-s-msn-com.akamaized.net:443 [http -> proxyA]
2024/01/12 08:55:37 127.0.0.1:8305 accepted //sb.scorecardresearch.com:443 [http -> proxyB]
2024/01/12 08:55:37 127.0.0.1:8306 accepted //th.bing.com:443 [http -> proxyC]
2024/01/12 08:55:37 127.0.0.1:8307 accepted //api.msn.cn:443 [http -> proxyA]
2024/01/12 08:55:37 127.0.0.1:8309 accepted //c.msn.cn:443 [http -> proxyB]
2024/01/12 08:55:38 127.0.0.1:8321 accepted //assets.msn.com:443 [http -> proxyC]
2024/01/12 08:55:39 127.0.0.1:8326 accepted //c.bing.com:443 [http -> proxyA]
2024/01/12 08:55:52 127.0.0.1:8366 accepted //edge.microsoft.com:443 [http -> proxyB]
2024/01/12 08:55:53 127.0.0.1:8370 accepted //prod-eastasia.access-point.cloudmessaging.edge.microsoft.com:443 [http -> proxyC]
2024/01/12 08:55:53 127.0.0.1:8373 accepted //edge.microsoft.com:443 [http -> proxyA]
2024/01/12 08:55:54 127.0.0.1:8375 accepted //www.bingapis.com:443 [http -> proxyB]
2024/01/12 08:55:54 127.0.0.1:8378 accepted //bzib.nelreports.net:443 [http -> proxyC]
2024/01/12 08:55:56 127.0.0.1:8385 accepted //cn.bing.com:443 [http -> proxyA]
2024/01/12 08:56:01 127.0.0.1:8393 accepted //sb.scorecardresearch.com:443 [http -> proxyB]

// 执行 xray.exe api rmo -s=127.0.0.1:10085 "proxyB"
2024/01/12 08:56:15 127.0.0.1:8416 accepted tcp:127.0.0.1:0 [api -> api]

// 执行 xray.exe api ado -s=127.0.0.1:10085 add.json
2024/01/12 08:56:27 127.0.0.1:8454 accepted tcp:127.0.0.1:0 [api -> api]

2024/01/12 08:56:35 127.0.0.1:8480 accepted //bing.com:443 [http -> proxyD]
2024/01/12 08:56:35 127.0.0.1:8479 accepted //bing.com:443 [http -> proxyE]
2024/01/12 08:56:35 127.0.0.1:8484 accepted //r.bing.com:443 [http -> proxyA]
2024/01/12 08:56:35 127.0.0.1:8483 accepted //r.bing.com:443 [http -> proxyC]
2024/01/12 08:56:36 127.0.0.1:8487 accepted //s.cn.bing.net:443 [http -> proxyD]
2024/01/12 08:56:38 127.0.0.1:8495 accepted //c.msn.cn:443 [http -> proxyE]
2024/01/12 08:56:38 127.0.0.1:8496 accepted //browser.events.data.msn.cn:443 [http -> proxyA]
2024/01/12 08:56:39 127.0.0.1:8501 accepted //login.microsoftonline.com:443 [http -> proxyC]
2024/01/12 08:56:39 127.0.0.1:8503 accepted //storage.live.com:443 [http -> proxyD]
2024/01/12 08:56:39 127.0.0.1:8504 accepted //browser.events.data.msn.cn:443 [http -> proxyE]
2024/01/12 08:56:39 127.0.0.1:8507 accepted //www2.bing.com:443 [http -> proxyA]
2024/01/12 08:56:40 127.0.0.1:8511 accepted //aadcdn.msftauth.net:443 [http -> proxyC]
2024/01/12 08:56:40 127.0.0.1:8513 accepted //login.live.com:443 [http -> proxyD]
2024/01/12 08:56:41 127.0.0.1:8519 accepted //www.msn.cn:443 [http -> proxyE]
2024/01/12 08:56:41 127.0.0.1:8522 accepted //login.live.com:443 [http -> proxyA]
2024/01/12 08:56:41 127.0.0.1:8524 accepted //assets.msn.cn:443 [http -> proxyC]
2024/01/12 08:56:44 127.0.0.1:8531 accepted //img-s.msn.cn:443 [http -> proxyD]
2024/01/12 08:56:44 127.0.0.1:8532 accepted //img-s.msn.cn:443 [http -> proxyE]
2024/01/12 08:56:44 127.0.0.1:8535 accepted //ts4.cn.mm.bing.net:443 [http -> proxyA]
2024/01/12 08:56:44 127.0.0.1:8537 accepted //ts4.cn.mm.bing.net:443 [http -> proxyC]
2024/01/12 08:56:44 127.0.0.1:8538 accepted //ts4.cn.mm.bing.net:443 [http -> proxyD]
2024/01/12 08:56:44 127.0.0.1:8539 accepted //ts4.cn.mm.bing.net:443 [http -> proxyE]
2024/01/12 08:56:44 127.0.0.1:8540 accepted //ts4.cn.mm.bing.net:443 [http -> proxyA]
2024/01/12 08:56:44 127.0.0.1:8541 accepted //ts4.cn.mm.bing.net:443 [http -> proxyC]
2024/01/12 08:56:45 127.0.0.1:8547 accepted //img-s.msn.cn:443 [http -> proxyD]
2024/01/12 08:56:45 127.0.0.1:8548 accepted //img-s.msn.cn:443 [http -> proxyE]

[yuhan6665]

懂了 感谢说明！

[deorth-kku]

https://github.com/vrnobody/Xray-core/blob/9151ed6c216cb9a298f1a70a001dceba1c24fabf/app/proxyman/outbound/outbound.go#L152-L172
我有个问题，这里access锁的是个RLock，但是有写入map的操作，不会出现并发写的问题吗？
实际上我这里已经遇到了
fatal error: concurrent map writes