Database Activity for Capacity Planning

 

Topic Last Modified: 2012-10-17

This section describes the database disk activity for the Microsoft Lync Server 2010 databases.

Front End Pool Databases

The following table lists the peak and average disk activity for the Front End pool databases, with 80,000 users in the pool.

Front End Pool Database Usage

Database	Peak usage in bytes per read and write	Average usage in bytes per read and write	Peak usage in reads and writes per second	Average usage in reads and writes per second
Back End data drive	Read: 65,536 bytes/read Write: 193,634.45 bytes/write	Read: 972.12 bytes/read Write: 3104.62 bytes/write	1.27 reads/second 3,553.79 writes/second	0 reads/second 143.91 writes/second
RTC log	Read: 61,440 bytes/read Write: 5,632 bytes/write	Read: 2106.05 bytes/read Write: 896.71 bytes/write	1.20 reads/second 161.41 writes/second	0 reads/second 45.34 writes/second
RTCdyn log	Read: 61,440 bytes/read Write: 10,011.6 bytes/write	Read 284.86 bytes/read Write: 4038.77 bytes/write	1.93 reads/second 499.3 writes/second	0 reads/second 330.93 writes/second
Tempdb data and log (see note following table)	Read: 65,536 bytes/read Write: 62,863.64 bytes/write	Read: 21,267.43 bytes/read Write: 59,383.11 bytes/write	15.73 reads/second 166.89 writes/second	0.31 reads/second 65.26 writes/second
RtcAb log (during nightly maintenance)	Read: 0 Write: 58,868.66 bytes/write	Read: 0 Write: 27,530.26 bytes/write	0 reads/second 586.97 writes/second	1.27 reads/second 43.77 writes/second

Note

For optimal performance, you should divide tempdb into multiple data files of equal size. These multiple files do not necessarily have to be on different disks or spindles unless you are also encountering I/O bottlenecks as well. The general recommendation is to have one file per CPU because only one thread is active per CPU at one time. For details about best practices, see https://go.microsoft.com/fwlink/p/?LinkId=205442.

Content Collaboration Database Usage

Category	Peak usage in bytes per read and write, 10,000 provisioned users	Average usage in bytes per read and write, 10,000 provisioned users	Average disk reads and writes per second, 10,000 provisioned users
Overall I/O rate for content collaboration	Read: 65,408 bytes/read Write: 158,067 bytes/write	Read: 1354 bytes/read Write: 13,902 bytes/write	0.17 reads/second 5.914 writes/second

Monitoring Server and Archiving Server Databases

Monitoring Server has separate databases for call detail records (CDRs) and Quality of Experience (QoE) data. With 240,000 users, the average database growth rate is 0.9 GB/hour for the CDR database, and 0.8 GB/hour for the QoE database. These numbers assume the Lync Server 2010 user model, where 50% of users are unified communications (UC) enabled.

For an Archiving Server supporting 240,000 users, the average database growth rate is 1.4GB/hour.

The following table lists the peak and average disk activity for the Monitoring Server and Archiving Server databases.

Category	Average bytes per read and bytes per write (240,000 users)	Peak bytes per read and bytes per write (240,000 users)	Disk reads and writes per second (240,000 users)
Collocated Monitoring and Archiving databases	Data drive (CDR data file, QoE data file, and Archiving data file): 8445 bytes/read 68,823 bytes/write Log drive (CDR log file and Archiving log file) 0 bytes/read 2951 bytes/write Log drive (QoE log file) 0 bytes/read 5378 bytes/write	Data drive (CDR data file, QoE data file, and Archiving data file): 60,000 bytes/read 646,323 bytes/write Log drive (CDR log file and Archiving log file) 0 bytes/read 4200 bytes/write Log drive (QoE log file) 0 bytes/read 6700 bytes/write	Data drive (CDR data file, QoE data file, and Archiving data file): 14.67 reads/second 709 writes/second Log drive (CDR log file and Archiving log file) 0 reads/second 678 writes/second Log drive (QoE log file) 0 reads/second 141 writes/second
Archiving database	Data drive: 1462 bytes/read 74,160 bytes/write Log drive 0 bytes/read 1770 bytes/write	Data drive: 14,336 bytes/read 1,000,000 bytes/write Log drive 0 bytes/read 3184 bytes/write	Data drive: 0.01 reads/second 172 writes/second Log drive 0 reads/second 736 writes/second
Monitoring database	Data drive (CDR data file and QoE data file): 18,271 bytes/read 47,384 bytes/write Log drive (CDR log file) 0 bytes/read 3402 bytes/write Log drive (QoE log file) 0 bytes/read 5871 bytes/write	Data drive (CDR data file and QoE data file): 65,405 bytes/read 1,722,052 bytes/write Log drive (CDR log file) 0 bytes/read 4982 bytes/write Log drive (QoE log file) 0 bytes/read 8892 bytes/write	Data drive (CDR data file and QoE data file): 145 reads/second 443 writes/second Log drive (CDR log file) 0 reads/second 367 writes/second Log drive (QoE log file) 0 reads/second 118 writes/second

The following table shows the disk usage for the archiving of content collaboration.

Content Collaboration Archiving Database Usage

Category	Peak usage in bytes per read and write, 10,000 provisioned users	Average usage in bytes per read and write, 10,000 provisioned users	Average disk reads and writes per second, 10,000 provisioned users
Content collaboration archiving	Read: 65,425 bytes/read Write: 106,389 bytes/write	Read: 1073 bytes/read Write: 6843 bytes/write	0.161 reads/second 25.491 writes/second