Giám sát bằng cách sử dụng System Monitor Ngoài việc sử dụng cơ sở dữ liệu Mirroring Monitor, bạn cũng có thể sử dụng System Monitor (trước đây gọi là Performance Monitor) để theo dõi hiệu suất phản ánh cơ sở dữ liệu. Các SQLServer: Cơ sở dữ liệu Mirroring đối tượng cơ sở dữ liệu chứa các bộ đếm hiệu suất phản chiếu. | Part VI Enterprise Data Management FIGURE 47-15 Monitoring a database mirroring session Monitoring using System Monitor Apart from using the Database Mirroring Monitor you can also use System Monitor previously referred to as Performance Monitor to monitor database mirroring performance. The SQLServer Database Mirroring object contains the database mirroring performance counters. The following list describes some of the key counters. Key principal server counters Log Bytes Sent sec Indicates the rate at which the principal is transferring transaction log records to the mirror. Log Send Queue KB Indicates the total number of transaction log kilobytes that have not been sent to the mirror yet. Transaction Delay Indicates the delay in milliseconds spent waiting for the commit acknowledgment from the mirror. This counter is useful for determining whether database mirroring is impacting performance on the principal server. 1112 Database Mirroring 47 FIGURE 47-16 Database mirroring history FIGURE 47-17 Setting warning thresholds 1113 Part VI Enterprise Data Management FIGURE 47-18 Database mirroring warnings Log Compressed Bytes Sent sec Indicates the number of compressed bytes of transaction log sent in the last second. To find the factor by which the transaction log stream has been compressed also referred to as log compression ratio divide the Log Bytes Sent sec by Log Compressed Bytes Sent sec. Log Bytes Sent from Cache sec Indicates how much of the transaction log bytes being sent from the principal to the mirror is being read from the principal s in-memory transaction log cache. Key mirror server counters Redo Bytes sec Indicates the rate at which log bytes are being rolled forward on the mirror database. Redo Queue KB Indicates the total number of transaction log kilobytes that have not been rolled forward to the mirror database yet. To estimate the time it will take the mirror to redo the log divide Redo Queue KB by Redo
