自己建网站要花多少钱,互联网行业分为哪几类,确实网站的建设目标,武平县网站建设一、服务实例过滤器ServerListFilter
服务实例过滤器#xff08;ServerListFilter#xff09;为负载均衡器#xff08;Loadbalancer#xff09;提供从服务实例列表#xff08;ServerList#xff09;获取的服务实例过滤出符合要求的服务实例。
负载均衡器#xff08;Lo…一、服务实例过滤器ServerListFilter
服务实例过滤器ServerListFilter为负载均衡器Loadbalancer提供从服务实例列表ServerList获取的服务实例过滤出符合要求的服务实例。
负载均衡器Loadbalancer通过服务实例列表ServerList从注册中心register或者配置文件yaml或properties上读取全部服务实例server然后以服务实例过滤器ServerListFilter的过滤方式进行筛选留下满足条件的服务实例进而借助负载均衡策略IRule选择出一个合适的服务实例。 二、ServerListFilter实现类 ZoneAffinityServerListFilter 区区域相关性筛选服务实例列表过滤器
ZonePreferenceServerListFilter 首选本地区域服务实例列表过滤器
ServerListSubsetFilter 服务实例数限制为所有服务实例的子集 筛选过滤器 三、具体代码实现
1ZoneAffinityServerListFilter
public class ZoneAffinityServerListFilterT extends Server extendsAbstractServerListFilterT implements IClientConfigAware {private volatile boolean zoneAffinity DefaultClientConfigImpl.DEFAULT_ENABLE_ZONE_AFFINITY;private volatile boolean zoneExclusive DefaultClientConfigImpl.DEFAULT_ENABLE_ZONE_EXCLUSIVITY;private DynamicDoubleProperty activeReqeustsPerServerThreshold;private DynamicDoubleProperty blackOutServerPercentageThreshold;private DynamicIntProperty availableServersThreshold;private Counter overrideCounter;private ZoneAffinityPredicate zoneAffinityPredicate new ZoneAffinityPredicate();private static Logger logger LoggerFactory.getLogger(ZoneAffinityServerListFilter.class);String zone;public ZoneAffinityServerListFilter() { }public ZoneAffinityServerListFilter(IClientConfig niwsClientConfig) {initWithNiwsConfig(niwsClientConfig);}Overridepublic void initWithNiwsConfig(IClientConfig niwsClientConfig) {String sZoneAffinity niwsClientConfig.getProperty(CommonClientConfigKey.EnableZoneAffinity, false);if (sZoneAffinity ! null){zoneAffinity Boolean.parseBoolean(sZoneAffinity);logger.debug(ZoneAffinity is set to {}, zoneAffinity);}String sZoneExclusive niwsClientConfig.getProperty(CommonClientConfigKey.EnableZoneExclusivity, false);if (sZoneExclusive ! null){zoneExclusive Boolean.parseBoolean(sZoneExclusive);}if (ConfigurationManager.getDeploymentContext() ! null) {zone ConfigurationManager.getDeploymentContext().getValue(ContextKey.zone);}activeReqeustsPerServerThreshold DynamicPropertyFactory.getInstance().getDoubleProperty(niwsClientConfig.getClientName() . niwsClientConfig.getNameSpace() .zoneAffinity.maxLoadPerServer, 0.6d);logger.debug(activeReqeustsPerServerThreshold: {}, activeReqeustsPerServerThreshold.get());blackOutServerPercentageThreshold DynamicPropertyFactory.getInstance().getDoubleProperty(niwsClientConfig.getClientName() . niwsClientConfig.getNameSpace() .zoneAffinity.maxBlackOutServesrPercentage, 0.8d);logger.debug(blackOutServerPercentageThreshold: {}, blackOutServerPercentageThreshold.get());availableServersThreshold DynamicPropertyFactory.getInstance().getIntProperty(niwsClientConfig.getClientName() . niwsClientConfig.getNameSpace() .zoneAffinity.minAvailableServers, 2);logger.debug(availableServersThreshold: {}, availableServersThreshold.get());overrideCounter Monitors.newCounter(ZoneAffinity_OverrideCounter);Monitors.registerObject(NIWSServerListFilter_ niwsClientConfig.getClientName());}private boolean shouldEnableZoneAffinity(ListT filtered) { if (!zoneAffinity !zoneExclusive) {return false;}if (zoneExclusive) {return true;}LoadBalancerStats stats getLoadBalancerStats();if (stats null) {return zoneAffinity;} else {logger.debug(Determining if zone affinity should be enabled with given server list: {}, filtered);ZoneSnapshot snapshot stats.getZoneSnapshot(filtered);double loadPerServer snapshot.getLoadPerServer();int instanceCount snapshot.getInstanceCount(); int circuitBreakerTrippedCount snapshot.getCircuitTrippedCount();if (((double) circuitBreakerTrippedCount) / instanceCount blackOutServerPercentageThreshold.get() || loadPerServer activeReqeustsPerServerThreshold.get()|| (instanceCount - circuitBreakerTrippedCount) availableServersThreshold.get()) {logger.debug(zoneAffinity is overriden. blackOutServerPercentage: {}, activeReqeustsPerServer: {}, availableServers: {}, new Object[] {(double) circuitBreakerTrippedCount / instanceCount, loadPerServer, instanceCount - circuitBreakerTrippedCount});return false;} else {return true;}}}Overridepublic ListT getFilteredListOfServers(ListT servers) {if (zone ! null (zoneAffinity || zoneExclusive) servers !null servers.size() 0){ListT filteredServers Lists.newArrayList(Iterables.filter(servers, this.zoneAffinityPredicate.getServerOnlyPredicate()));if (shouldEnableZoneAffinity(filteredServers)) {return filteredServers;} else if (zoneAffinity) {overrideCounter.increment();}}return servers;}Overridepublic String toString(){StringBuilder sb new StringBuilder(ZoneAffinityServerListFilter:);sb.append(, zone: ).append(zone).append(, zoneAffinity:).append(zoneAffinity);sb.append(, zoneExclusivity:).append(zoneExclusive);return sb.toString(); }
}
2ZonePreferenceServerListFilter
public class ZonePreferenceServerListFilter extends ZoneAffinityServerListFilterServer {private String zone;Overridepublic void initWithNiwsConfig(IClientConfig niwsClientConfig) {super.initWithNiwsConfig(niwsClientConfig);if (ConfigurationManager.getDeploymentContext() ! null) {this.zone ConfigurationManager.getDeploymentContext().getValue(ContextKey.zone);}}Overridepublic ListServer getFilteredListOfServers(ListServer servers) {ListServer output super.getFilteredListOfServers(servers);if (this.zone ! null output.size() servers.size()) {ListServer local new ArrayList();for (Server server : output) {if (this.zone.equalsIgnoreCase(server.getZone())) {local.add(server);}}if (!local.isEmpty()) {return local;}}return output;}public String getZone() {return zone;}public void setZone(String zone) {this.zone zone;}Overridepublic boolean equals(Object o) {if (this o) {return true;}if (o null || getClass() ! o.getClass()) {return false;}ZonePreferenceServerListFilter that (ZonePreferenceServerListFilter) o;return Objects.equals(zone, that.zone);}Overridepublic int hashCode() {return Objects.hash(zone);}Overridepublic String toString() {return new StringBuilder(ZonePreferenceServerListFilter{).append(zone).append(zone).append().append(}).toString();}}
3ServerListSubsetFilter
public class ServerListSubsetFilterT extends Server extends ZoneAffinityServerListFilterT implements IClientConfigAware, ComparatorT{private Random random new Random();private volatile SetT currentSubset Sets.newHashSet(); private DynamicIntProperty sizeProp new DynamicIntProperty(DefaultClientConfigImpl.DEFAULT_PROPERTY_NAME_SPACE .ServerListSubsetFilter.size, 20);private DynamicFloatProperty eliminationPercent new DynamicFloatProperty(DefaultClientConfigImpl.DEFAULT_PROPERTY_NAME_SPACE .ServerListSubsetFilter.forceEliminatePercent, 0.1f);private DynamicIntProperty eliminationFailureCountThreshold new DynamicIntProperty(DefaultClientConfigImpl.DEFAULT_PROPERTY_NAME_SPACE .ServerListSubsetFilter.eliminationFailureThresold, 0);private DynamicIntProperty eliminationConnectionCountThreshold new DynamicIntProperty(DefaultClientConfigImpl.DEFAULT_PROPERTY_NAME_SPACE .ServerListSubsetFilter.eliminationConnectionThresold, 0);Overridepublic void initWithNiwsConfig(IClientConfig clientConfig) {super.initWithNiwsConfig(clientConfig);sizeProp new DynamicIntProperty(clientConfig.getClientName() . clientConfig.getNameSpace() .ServerListSubsetFilter.size, 20);eliminationPercent new DynamicFloatProperty(clientConfig.getClientName() . clientConfig.getNameSpace() .ServerListSubsetFilter.forceEliminatePercent, 0.1f);eliminationFailureCountThreshold new DynamicIntProperty( clientConfig.getClientName() . clientConfig.getNameSpace() .ServerListSubsetFilter.eliminationFailureThresold, 0);eliminationConnectionCountThreshold new DynamicIntProperty(clientConfig.getClientName() . clientConfig.getNameSpace() .ServerListSubsetFilter.eliminationConnectionThresold, 0);}/*** Given all the servers, keep only a stable subset of servers to use. This method* keeps the current list of subset in use and keep returning the same list, with exceptions* to relatively unhealthy servers, which are defined as the following:* p* ul* liServers with their concurrent connection count exceeding the client configuration for * {code clientName.nameSpace.ServerListSubsetFilter.eliminationConnectionThresold} (default is 0)* liServers with their failure count exceeding the client configuration for * {code clientName.nameSpace.ServerListSubsetFilter.eliminationFailureThresold} (default is 0)* liIf the servers evicted above is less than the forced eviction percentage as defined by client configuration* {code clientName.nameSpace.ServerListSubsetFilter.forceEliminatePercent} (default is 10%, or 0.1), the* remaining servers will be sorted by their health status and servers will worst health status will be* forced evicted.* /ul* p* After the elimination, new servers will be randomly chosen from all servers pool to keep the* number of the subset unchanged. * */Overridepublic ListT getFilteredListOfServers(ListT servers) {ListT zoneAffinityFiltered super.getFilteredListOfServers(servers);SetT candidates Sets.newHashSet(zoneAffinityFiltered);SetT newSubSet Sets.newHashSet(currentSubset);LoadBalancerStats lbStats getLoadBalancerStats();for (T server: currentSubset) {// this server is either down or out of serviceif (!candidates.contains(server)) {newSubSet.remove(server);} else {ServerStats stats lbStats.getSingleServerStat(server);// remove the servers that do not meet health criteriaif (stats.getActiveRequestsCount() eliminationConnectionCountThreshold.get()|| stats.getFailureCount() eliminationFailureCountThreshold.get()) {newSubSet.remove(server);// also remove from the general pool to avoid selecting them againcandidates.remove(server);}}}int targetedListSize sizeProp.get();int numEliminated currentSubset.size() - newSubSet.size();int minElimination (int) (targetedListSize * eliminationPercent.get());int numToForceEliminate 0;if (targetedListSize newSubSet.size()) {// size is shrinkingnumToForceEliminate newSubSet.size() - targetedListSize;} else if (minElimination numEliminated) {numToForceEliminate minElimination - numEliminated; }if (numToForceEliminate newSubSet.size()) {numToForceEliminate newSubSet.size();}if (numToForceEliminate 0) {ListT sortedSubSet Lists.newArrayList(newSubSet); Collections.sort(sortedSubSet, this);ListT forceEliminated sortedSubSet.subList(0, numToForceEliminate);newSubSet.removeAll(forceEliminated);candidates.removeAll(forceEliminated);}// after forced elimination or elimination of unhealthy instances,// the size of the set may be less than the targeted size,// then we just randomly add servers from the big poolif (newSubSet.size() targetedListSize) {int numToChoose targetedListSize - newSubSet.size();candidates.removeAll(newSubSet);if (numToChoose candidates.size()) {// Not enough healthy instances to choose, fallback to use the// total server poolcandidates Sets.newHashSet(zoneAffinityFiltered);candidates.removeAll(newSubSet);}ListT chosen randomChoose(Lists.newArrayList(candidates), numToChoose);for (T server: chosen) {newSubSet.add(server);}}currentSubset newSubSet; return Lists.newArrayList(newSubSet); }/*** Randomly shuffle the beginning portion of server list (according to the number passed into the method) * and return them.* * param servers* param toChoose* return*/private ListT randomChoose(ListT servers, int toChoose) {int size servers.size();if (toChoose size || toChoose 0) {return servers;} for (int i 0; i toChoose; i) {int index random.nextInt(size);T tmp servers.get(index);servers.set(index, servers.get(i));servers.set(i, tmp);}return servers.subList(0, toChoose); }/*** Function to sort the list by server health condition, with* unhealthy servers before healthy servers. The servers are first sorted by* failures count, and then concurrent connection count.*/Overridepublic int compare(T server1, T server2) {LoadBalancerStats lbStats getLoadBalancerStats();ServerStats stats1 lbStats.getSingleServerStat(server1);ServerStats stats2 lbStats.getSingleServerStat(server2);int failuresDiff (int) (stats2.getFailureCount() - stats1.getFailureCount());if (failuresDiff ! 0) {return failuresDiff;} else {return (stats2.getActiveRequestsCount() - stats1.getActiveRequestsCount());}}
}
