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IO - Bufferpools

Purpose

Buffer pool hit ratios are one of the most fundamental metrics for measuring database performance.  They provide an important overall measure of how effectively the system is exploiting memory to avoid disk IO.  This view shows hit ratios for all buffer pools and for various data types.

IO-Bufferpools.png

Metrics Shown in Grid

In the grid portion of the view, we show the hit ratio and key metrics for each buffer pool, including size and number of logical and physical reads.  In the summary and gauges above the grid, we show some of the same metrics summarized across all buffer pools.

BufferPool Name

Source: mon_get_bufferpool.bp_name


Delta l_reads/s

Source: mon_get_bufferpool

Delta p_reads/s

Source: mon_get_bufferpool

pool_data_p_reads + pool_index_p_reads + pool_xda_p_reads + pool_col_p_reads +

pool_temp_data_p_reads + pool_temp_index_p_reads + pool_temp_xda_p_reads + pool_temp_col_p_reads


Hit Ratio %


Async Reads %


Delta Bp Writes/s

Source: mon_get_bufferpool

pool_data_writes + pool_index_writes + pool_xda_writes + pool_col_writes


Delta Direct Writes/s

Source: mon_get_activity.direct_writes


Delta a_reads/s
Async ReadMs
Delta a_writes/s
Async WrtMs
Async Wrt %
# of DBP

For this bufferpool, the number of database partitions for which buffer pool information is being reported.


BP Pages
Files Closed/s
Block IOs/s
Pages BlkIOs/s
Vectored IOs/s
Pages VctIOs/s
Victim Pages/s
Unread PrefPages/s
%Unread PrefPages
XDA l_reads/s
XDA p_reads/s
XDA writes/s

Default Sort Column

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Author: KevinLBeck