NetWorker：如何使用 ddboost_precert.log 分析 IO 性能

Summary: 本文提供有关如何使用 precert-io-perf.py Python 脚本从 ddboost_precert.log 文件分析 I/O 性能的分步说明。该脚本计算写入和读取操作的各种统计信息，包括持续时间和吞吐量 （MB/s），并提供技术和非技术利益相关者可理解的综合摘要。

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Instructions

当 NetWorker Client Direct 备份问题被认为与客户端的 Data Domain DD Boost 库相关时，系统会在故障处理步骤中启用 Precert 日志记录。此实用程序可以从收集的预认证日志中识别性能问题。


准备ddboost_precert.log

作为一个简单的使用示例，创建 ddboost_precert.ini 在 UNIX 根目录或 C：\ for Windows 的根目录上。该文件应包含：  
precert_enabled=true
num_log_files=4
log_file_size=512
log_file_name=ddboost_precert.log
log_file_dir=/DDLog
ddcl_logs_include=true
ddcl_logs_sev=4
请参阅文章 Data Domain：使用 precert 工具（precert 日志）启用 DD Boost API 日志记录，以获取收集 precert 日志的完整过程详细信息。（需要登录戴尔支持才能查看本文）


准备使用脚本

前提条件：  Python 3.x
从以下位置下载脚本：解决方案 NetWorker 工具 （dell.com）
  1. 将脚本保存到包含预认证日志的工作目录，该目录为 precert-io-perf.py。
  2. 在 UNIX 系统上，确保脚本是可执行文件： chmod +x precert-io-perf.py
  3. 运行脚本： ./precert-io-perf.py

输入提示符

  • 出现提示时，输入 DD Boost precert 日志文件的完整路径。
  • 当系统提示您是否为每个 I/O 操作包括 MB/s 时，输入“ Yes ”或 “No ”

输出摘要

该脚本显示写入和读取操作的摘要，包括：
  • 写入和读取操作的总数
  • 平均写入和读取持续时间
  • 最大和最小写入和读取持续时间及其各自的吞吐量（MB/秒）
  • 总写入和读取时间
  • 写入和读取所花费的总时间百分比
  • 平均写入和读取吞吐量（MB/秒）
  • 详细的 I/O 操作
脚本将详细的 I/O 操作记录到两个 CSV 文件中：
  • io-write.log — 包含有关每个写入操作的详细信息
  • io-read.log — 包含有关每个读取操作的详细信息


输出示例

# ./precert-io-perf.py
Please enter the full path to the log file: ./ddboost_precert.log
Do you want to include MB/s for each I/O operation? (yes/no): yes

    Write Durations Summary:

    Total number of write operations: 2646
    Average write duration: 0.005389 seconds
    Maximum write duration: 0.041000 seconds (24.39 MB/s)
    Minimum write duration: 0.000001 seconds (1000000.00 MB/s)
    Total write time: 14.259001 seconds
    Percentage of total time spent on writes: 22.99%
    Average write throughput: 185.566997 MB/s
    Note: High MB/s values for very short durations indicate efficient operations.


    Read Durations Summary:

    Total number of read operations: 2651
    Average read duration: 0.018018 seconds
    Maximum read duration: 31.838000 seconds (0.03 MB/s)
    Minimum read duration: 0.001000 seconds (1000.00 MB/s)
    Total read time: 47.766000 seconds
    Percentage of total time spent on reads: 77.01%
    Average read throughput: 55.499728 MB/s
    Note: High MB/s values for very short durations indicate efficient operations.


Top 20 Slowest Write I/O Operations:
1. I/O Number: 608, Duration: 0.041000 seconds, MB/s: 24.39
2. I/O Number: 2276, Duration: 0.038000 seconds, MB/s: 26.32
3. I/O Number: 1548, Duration: 0.025000 seconds, MB/s: 40.00
4. I/O Number: 2076, Duration: 0.025000 seconds, MB/s: 40.00
5. I/O Number: 636, Duration: 0.024000 seconds, MB/s: 41.67
6. I/O Number: 195, Duration: 0.023000 seconds, MB/s: 43.48
7. I/O Number: 892, Duration: 0.023000 seconds, MB/s: 43.48
8. I/O Number: 1451, Duration: 0.023000 seconds, MB/s: 43.48
9. I/O Number: 1539, Duration: 0.023000 seconds, MB/s: 43.48
10. I/O Number: 1987, Duration: 0.023000 seconds, MB/s: 43.48
11. I/O Number: 604, Duration: 0.022000 seconds, MB/s: 45.45
12. I/O Number: 896, Duration: 0.022000 seconds, MB/s: 45.45
13. I/O Number: 1283, Duration: 0.022000 seconds, MB/s: 45.45
14. I/O Number: 1532, Duration: 0.022000 seconds, MB/s: 45.45
15. I/O Number: 1544, Duration: 0.022000 seconds, MB/s: 45.45
16. I/O Number: 595, Duration: 0.021000 seconds, MB/s: 47.62
17. I/O Number: 616, Duration: 0.021000 seconds, MB/s: 47.62
18. I/O Number: 652, Duration: 0.021000 seconds, MB/s: 47.62
19. I/O Number: 1512, Duration: 0.021000 seconds, MB/s: 47.62
20. I/O Number: 1552, Duration: 0.021000 seconds, MB/s: 47.62

Top 20 Slowest Read I/O Operations:
1. I/O Number: 5900, Duration: 31.838000 seconds, MB/s: 0.03
2. I/O Number: 1614, Duration: 0.041000 seconds, MB/s: 24.39
3. I/O Number: 4950, Duration: 0.039000 seconds, MB/s: 25.64
4. I/O Number: 4550, Duration: 0.026000 seconds, MB/s: 38.46
5. I/O Number: 1670, Duration: 0.025000 seconds, MB/s: 40.00
6. I/O Number: 3494, Duration: 0.025000 seconds, MB/s: 40.00
7. I/O Number: 788, Duration: 0.023000 seconds, MB/s: 43.48
8. I/O Number: 1606, Duration: 0.023000 seconds, MB/s: 43.48
9. I/O Number: 2182, Duration: 0.023000 seconds, MB/s: 43.48
10. I/O Number: 3300, Duration: 0.023000 seconds, MB/s: 43.48
11. I/O Number: 3476, Duration: 0.023000 seconds, MB/s: 43.48
12. I/O Number: 3486, Duration: 0.023000 seconds, MB/s: 43.48
13. I/O Number: 4372, Duration: 0.023000 seconds, MB/s: 43.48
14. I/O Number: 2190, Duration: 0.022000 seconds, MB/s: 45.45
15. I/O Number: 2964, Duration: 0.022000 seconds, MB/s: 45.45
16. I/O Number: 3422, Duration: 0.022000 seconds, MB/s: 45.45
17. I/O Number: 3462, Duration: 0.022000 seconds, MB/s: 45.45
18. I/O Number: 4628, Duration: 0.022000 seconds, MB/s: 45.45
19. I/O Number: 5548, Duration: 0.022000 seconds, MB/s: 45.45
20. I/O Number: 1588, Duration: 0.021000 seconds, MB/s: 47.62
Detailed I/O operations have been logged to io-write.log and io-read.log


example of above analysis:

Percentage of total time spent on writes: 22.99%
Percentage of total time spent on reads: 77.01%

此示例演示数据的读取操作（而非写入操作）如何出现性能问题。

Affected Products

Data Domain Boost, NetWorker
Article Properties
Article Number: 000227597
Article Type: How To
Last Modified: 05 Sep 2024
Version:  2
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