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Top Consumers - Connections

Purpose

Find the connections (sessions) that have consumed the most resources over their lifetime.  This view is helpful for diagnosing problems where large numbers of small activities in aggregate are consuming excessive resources.  A common scenario of this type is applications loading data one row at a time using singleton inserts.  This can be very disruptive but each individual insert is tiny and so is the singleton transaction associated with it.  This view will highlight connections engaged in these sort of activities.

Note that this overlaps somewhat in functionality with the Sessions (connections) view.  If you go to the connections view, in counter mode, you could select various columns one at a time and sort by them to find the connections that have consumed the most CPU, read the most rows, etc.  This view provides a convenient way to get similar information in one step.

TopConsumers-Connections.png

Histograms and Summaries (Gauges)

<link TBD>

Metrics Shown

There is a grid, with a row for each resource that is tracked.  Each row names the resource and shows

  • Item no, so that the user can use sort to restore the grid to its canonical ordering if it has been sorted on some other column.
  • Server resource (CPU, Rows Read, etc.)
  • The application handle for the connection that has consumed the most of this resource.
  • What percentage of the resource this particular connection has consumed, relative to consumption by other connections.
  • How many rows read, CPU seconds used, etc.
  • The name of the application associated with this connection.
  • SQL text of most recently executed statement, if available.

0  CPU Time

Source: mon_get_connection.total_cpu_time


1  Rows Read

Source: mon_get_connection.rows_read


2  Rows Returned

Source: mon_get_connection.rows_returned


3  Rows Written

Source: mon_get_connection.rows_modified


4  Logical Reads


5  IO r/w


6  Memory


7  Sort time

Source: mon_get_connection.total_section_sort_time


8  Num sorts

Source: mon_get_connection.total_sorts


9  Sort overflows

Source: mon_get_connection.sort_overflows


10 Num threshold violations

Source: mon_get_connection.thresh_violations


11 FCM Traffic

fcm_send_volume + fcm_recv_volume


12 Num agents

Source: mon_get_connection.num_assoc_agents


13 Num locks held

Source: mon_get_connection.num_locks_held


14 Lock Escalations

Source: mon_get_connection.lock_escals


15 Lock timeouts

Source: mon_get_connection.lock_timeouts


16 Lock Waits

Source: mon_get_connection.lock_waits


17 Lock Wait Time

Source: mon_get_connection.lock_wait_time


18 Lock Wait Time (Global)

Source: mon_get_connection.lock_wait_time_global


19 Lock waits (global)

Source: mon_get_connection.lock_waits_global


20 CF Wait Time

Source: mon_get_connection.cf_wait_time


21 CF Waits

Source: mon_get_connection.cf_waits

Default Sort Column

Item No, ascending

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Author: KevinLBeck