问题现象 应用服务异常：业务应用性能下降，服务响应超时，或出现与I/O相关的错误日志。监控指标告警：云监控显示磁盘的%util（使用率）指标接近或持续处于100%，或收到磁盘IOPS、吞吐量超阈值的告警。问题原因 高I/O消耗进程：实例内部...
This topic describes how to troubleshoot the issues that cause high I/O on an ApsaraDB RDS for MySQL instance.The I/O performance of your RDS instance varies based on the storage type,kernel architecture,and SQL statement ...
If the disk I/O becomes a performance bottleneck of your ApsaraDB RDS for PostgreSQL instance,you can use the I/O acceleration feature to resolve the performance bottleneck.This topic describes the benefits,scenarios,and ...
000 I/O operations.If the number of I/O operations is lower than 10,000,the fee is calculated as if 10,000 I/O operations were performed.Procedure Enable the I/O burst feature when you create a PolarDB for MySQL cluster Go...
Storage I/O performance refers to the speed and efficiency with which cloud disks handle read and write requests.Storage I/O performance metrics are important indicators of how well your storage devices perform and handle ...
effective.General ESSDs use high performance disks as scalable resources to increase I/O rates.General ESSDs use AliSQL to respond to I/O bursts during database reads and writes.Data that is infrequently accessed is ...
2 系统将请求通信对象递交给I/O线程，并在I/O线程中完成编码。3 编码完成后，将内容传递到服务提供方的I/O线程。客户端线程会等待结果返回。4 服务提供方的I/O线程接收到二进制内容，解码后生成通信请求对象，并将其递交给HSF服务端线程。5...
背景信息 ⼀般云数据库厂商为了避免宿主机出现I/O争抢，会使⽤CGroup（Control Groups）等技术进⾏实例间的I/O隔离和IOPS（Input/Output Operations Per Second）限制，即不同规格的实例配置对应不同的IOPS使⽤上限。注意事项 MongoDB单...
I/O acceleration,and data archiving features.I/O acceleration After you enable the I/O acceleration feature,the system expands the size of the buffer pool of your RDS instance.This accelerates caching and improves the read...
您可以通过polar_stat_io_info视图和polar_stat_io_latency视图查看I/O统计信息和I/O延迟分布信息。说明 使用I/O统计视图和I/O延迟分布视图需要在数据库中创建 polar_monitor 插件，您可以使用 CREATE EXTENSION polar_monitor 创建。I/O...
This topic describes I/O performance optimization of DDL statements.PolarDB uses the compute and storage decoupled architecture.Compute nodes use high-performance RDMA to access distributed storage.However,the latency of ...
小 I/O 操作频繁 在小 I/O 场景下，频繁的4 KB小 I/O 操作会导致写入效率低下。将小 I/O 聚合成较大的 I/O 操作，以提高传输效率。文件夹内文件数过多 在同一文件夹内写入大量文件（如几十万个）可能导致目录锁，进而影响写入性能。建议将...
当实例I/O压力较大时，大量的WAL日志读I/O和日常业务的读写I/O会互相影响I/O时延，日常业务的运行速度会变慢，复制延时也会变大。原生PostgreSQL中，WAL日志产生时，会先被写入到WAL Buffer中，然后再被后台进程或普通进程写入存储。WAL ...
当实例I/O压力较大时，大量的WAL日志读I/O和日常业务的读写I/O会互相影响I/O时延，日常业务的运行速度会变慢，复制延时也会变大。原生PostgreSQL中，WAL日志产生时，会先被写入到WAL Buffer中，然后再被后台进程或普通进程写入存储。WAL ...
如果ESSD云盘的性能总和超过了实例规格族所对应的存储I/O能力，实际存储性能以该实例规格对应的存储I/O能力为准。例如，当您创建了ecs.g7se.xlarge 16GiB规格实例后，该实例最大存储IOPS为6万。如果挂载了1块存储I/O能力为2 TiB的ESSD云盘...
This topic describes the content of the health report of an E-MapReduce(EMR)Serverless StarRocks instance.This topic also explains the fields in the health report.Health reports are generated with a delay of one day.A ...
IOPS与 IO带宽 间的制约关系 云盘IOPS与IO带宽并非独立的性能指标，除共同受实例规格、存储类型和存储空间影响外，两者之间也会互相制约：换算公式：IO带宽(MB/s)=IOPS×I/O块大小(KB)/1024（此处I/O块大小指磁盘单次I/O操作大小（云盘默认...
only RDS MySQL instances that run RDS High-availability Edition support Premium Local SSDs.Metric Premium Local SSD Premium performance disk ESSD I/O performance★Delivers low I/O latency and high I/O performance:IOPS:...
I/O reactor status:STOPPED Possible cause The Tablestore client is shut down and the internal I/O reactors are also shut down.Solution Check whether the Tablestore client is shut down.If the Tablestore client is shut down,...
the disk size is small,and the disk I/O usage is high.The following table describes the features of general ESSDs.I/O burst I/O acceleration Storage capacity reduction for ApsaraDB RDS for MySQL instances that use cloud ...
mq-deadline,kyber,bfq,and none.Replace the current I/O scheduler bfq with another I/O scheduler.Replace the current I/O scheduler bfq with another I/O scheduler.For example,you can replace bfq with mq-deadline.Run the sudo...
指标高：CPU、内存、磁盘I/O监控持续超过80%。服务中断：关键进程被系统终止（OOM），实例自动重启。无法登录：SSH连接被拒绝。问题原因 程序问题：应用代码存在性能瓶颈或内存泄漏。流量突增：并发访问超出实例处理能力。I/O瓶颈：磁盘...
the maximum memory of a single PolarDB cluster can reach 10 TB.The 16 KB random read I/O latency is as low as 10 us,which is approximately one-tenth of the storage I/O latency.This significantly improves performance in I/O...
clog_io_byte The average I/O throughput per second of the log disk of the node.Unit:MB.OB Clog IO Util ob_clog_io_util The I/O usage of the log disk of the node in percentage(%).OB Data Disk IOPS ob_data_io The average ...
The/proc/diskstats raw data source interface of the iostat I/O latency analysis tool is optimized in Alibaba Cloud Linux to calculate the amount of time consumed by read,write,and special I/O(discard)operations on devices....
clog_io_util I/O usage of the log disk of the OBServer node.Host Metrics ob_data_io Average number of I/O operations per second on the data disk of the OBServer node.Host Metrics ob_data_io_read Average number of I/O reads...
The DDL asynchronous I/O feature is added in PolarDB.It is time-consuming to create indexes in large tables by executing the DDL statement.You can use the DDL asynchronous I/O feature to shorten the time to create indexes....
Supports the I/O performance burst and BPE features in addition to all features of ESSDs.The following list describes the I/O performance of Premium ESSDs:IOPS:varies based on the disk specifications and instance types.I...
Cause The I/O optimization property of the instance must match that of the image.I/O optimized instances can use only I/O optimized images,and non-I/O optimized instances can use only non-I/O optimized images.Therefore,if ...
burst_ratio%The percentage of disk I/O throughput improvement after I/O burst is enabled.Throughput mBps_total MB/s The disk I/O throughput per second.mBps_read MB/s The disk read I/O throughput per second.mBps_write MB/s ...
view Storage Type.Comparison between storage types Table 1.Performance comparison Storage type I/O performance Flexible specifications Scalability Local SSD★Provides low I/O latency and high I/O performance.Provides ...
high I/O performance and low I/O latency High I/O performance and low I/O latency Moderate I/O performance and relatively low I/O latency Moderate I/O performance and relatively low I/O latency Capacity range(GiB)1,261 to ...
Note:NOT all instance types support VPC network and I/O optimization.Generation I Instance Type CPU/Memory I/O Optimization ecs.s1.small 1C 2G For SG ecs.s2.large 2C 4G For US East/Hong Kong(China)/SG ecs.s3.large 4C 8G ...
IOPS与 IO带宽 间的制约关系 云盘IOPS与IO带宽并非独立的性能指标，除共同受实例规格、存储类型和存储空间影响外，两者之间也会互相制约：换算公式：IO带宽(MB/s)=IOPS×I/O块大小(KB)/1024（此处I/O块大小指磁盘单次I/O操作大小（云盘默认...
An Elastic Compute Service(ECS)instance may experience the high I/O load issue due to factors such as excessive business load,unexpected non-business process occupation,or insufficient memory resources.The issue may cause ...