Lustre monitoring tool (LMT) disk usage and space requirements for CLE 6.x.
LMT requires at least 40GB persistent storage attached to the LMT server (i.e., the MGS) to store historical data. If the storage becomes full, data can be deleted from the database using MySQL delete statements.
MySQL Tables
Five tables store general file system statistics. These tables are populated by
lmt_agg.cron script.
Table 1. General File System Tables| Table Name | On-Disk Growth Rate |
|---|
FILESYSTEM_AGGREGATE_HOUR | 0.8 KB/hour |
FILESYSTEM_AGGREGATE_DAY | 0.8 KB/day |
FILESYSTEM_AGGREGATE_WEEK | 0.8 KB/week |
FILESYSTEM_AGGREGATE_MONTH | 0.8 KB/month |
FILESYSTEM_AGGREGATE_YEAR | 0.8 KB/year |
Table 2. MDS Aggregate Tables and Growth Rates| Table Name | Approximate On-Disk Growth Rate |
|---|
MDS_AGGREGATE_HOUR | 0.5 KB/hour/MDS |
MDS_AGGREGATE_DAY | 0.5 KB/day/MDS |
MDS_AGGREGATE_WEEK | 0.5 KB/week/MDS |
MDS_AGGREGATE_MONTH | 0.5 KB/month/MDS |
MDS_AGGREGATE_YEAR | 0.5 KB/year/MDS |
Table 3. OST Aggregate Tables and Growth Rates| Table Name | On-Disk Growth Rate |
|---|
OST_AGGREGATE_HOUR | 0.7 KB/hour/OST |
OST_AGGREGATE_DAY | 0.7 KB/day/OST |
OST_AGGREGATE_WEEK | 0.7 KB/week/OST |
OST_AGGREGATE_MONTH | 0.7 KB/month/OST |
OST_AGGREGATE_YEAR | 0.7 KB/year/OST |
Calculate Expected Disk Usage for a File System
Use this formula to calculate the approximate rate of disk space usage for a file system. Disregard the
AGGREGATE tables as they grow so much more slowly than the raw data tables.
(56 KB/hour/filesystem) * (# of filesystems) + (1000 KB/hour/MDS) * (# of MDSs)
+ (44 KB/hour/OSS) * (# of OSSs) + (70 KB/hour/OST) * (# of OSTs) = Total KB/hour
Calculate the Disk Usage for a File System for 1 Year
In this example, LMT is monitoring one file system with one MDS, four object storage servers (OSS), and eight object storage targets (OST). The amount of disk space used by the LMT database to is expected to grow at this hourly rate.56 KB/hour/filesystem * 1 filesystem + 1000 KB/hour/MDS * 1 MDS
+ 44 KB/hour/OSS * 4 OSSs + 70 KB/hour/OST * 8 OSTs = 1792 KB/hour
Which translates to this yearly rate.1792 KB/hour * 24 hours/day * 365 days/year * 1 MB/1024KB
* 1 GB/1024MB = 15 GB / year