Help for Foxhound 2.0.4215a

Table of Contents    [RisingRoad]


4. The History Page

The History page shows previous server and database-level performance statistics for a target database, as well as information about individual connections. This information is collectively referred to as a "sampling session" because it is gathered (sampled) at regular intervals rather than recorded on a continuous basis.

The History page looks just like the Monitor Database page, except...

4.1 The History Menu

4.2 The History Status Area

4.3 Top Sample

4.4 Peaks

4.5 Samples

4.6 Blocked Connections

4.7 Connections


4.1 The History Menu    [Top]


« Back to Menu DSN: ddd12 New Menu Schema Monitor Foxhound Options Monitor Options About

The « Back to Menu link displays the main Foxhound menu page in the current browser window or tab.

The DSN: / Connection String: title shows the name of the DSN or Connection String that you used to connect to the target database. This identifies the "current target database", a term used in this Help.

Multiple History pages that display the same DSN or Connection String show the same data; they do not represent separate sampling sessions.

If the target database GlobalDBId property is set to a non-default value, that value will be shown in (parentheses) after the DSN: or Connection String: title. This makes it easier to tell different remote databases apart in a replicating or synchronizing environment.

The New Menu link opens the main Foxhound menu page in a new browser window or tab.

The Schema link opens the Display Schema page for this target database in a new browser window or tab.

The Monitor link opens the Monitor Database page for this sampling session in a new browser window or tab.

The Foxhound Options link opens the Foxhound Options page in a new browser window or tab.

The Monitor Options link opens the Monitor Options page in a new browser window or tab.

The button is a context-sensitive link to this Help topic. This button appears in many locations, each of them a link to a different Help topic in this frame.

Tip: To hide the Help for every new page, see the Show Help section on the Foxhound Options page.

The About link opens the About Foxhound page in a new browser window or tab.


Newest 500 100 20 1 sample Message Month Week Day 3 Hours 1 Hour

Newest - Scroll to the most recent samples for this database

Tip: Click on Newest to scroll to the "new top". If sampling is running, new samples will continue to be gathered, and the History page won't automatically show them unless you scroll up.

500 - Scroll up by 500 to more recent samples for this database

100 - Scroll up by 100 to more recent samples for this database

20 - Scroll up by 20 to more recent samples for this database

1 sample - Scroll up by 1 to more recent samples for this database

Message - Scroll up to the next most recent sample that has an Alert, AutoDrop or other message

Month - Scroll up by one month to more recent samples for this database

Week - Scroll up by one week to more recent samples for this database

Day - Scroll up by one day to more recent samples for this database

3 Hours - Scroll up by three hours to more recent samples for this database

1 Hour - Scroll up by one hour to more recent samples for this database


Message 1 sample 20 100 500 Oldest Freeze Frame Heights 1 Hour 3 Hours Day Week Month Go to:

Message - Scroll down to the next older sample that has an Alert, AutoDrop or other message

1 sample - Scroll down by 1 to older samples for this database

20 - Scroll down by 20 to older samples for this database

100 - Scroll down by 100 to older samples for this database

500 - Scroll down by 500 to older samples for this database

Oldest - Scroll down to the oldest sample for this database

Click on Freeze Frame Heights to stop Foxhound from resetting the frame heights each time to you scroll up or down or jump to a different sample.

1 Hour - Scroll down by one hour to older samples for this database

3 Hours - Scroll down by three hours to older samples for this database

Day - Scroll down by one day to older samples for this database

Week - Scroll down by one week to older samples for this database

Month - Scroll down by one month to older samples for this database

The Go to: field lets you scroll to a specific sample date/time or sample number. You don't have to be precise, the History page will scroll to the point nearest the value you typed.

The Go to: value is checked to see if it's a valid number first, then a date/time, so "Go to: 20120601" interpreted as a sample number rather than a sample date/time.

Goto: 1 works like Oldest.

Goto: 0 works like Oldest.

Goto: -1 is ignored, as are all values other than non-negative integers and valid date/times.

Go to: 1901-01-01 works like Oldest.

Go to: 9999999999999 works like Newest.

Go to: 2999-01-01 works like Newest.


4.2 The History Status Area    [Top]

The two-line date/time at the left tells you when this page was displayed.

The Server version: tells you what version of SQL Anywhere software was being used to run the target database when the Top Sample was recorded. This is based on the ProductVersion property.

Was using n CPUs tells you how many CPUs were being used to run the target database when the Top Sample was recorded.

This field is based on the NumLogicalProcessorsUsed and NumProcessorsAvail properties.

The Was running for field tells you how long the target server had been running when the Top Sample was recorded. For example, 32d 7h 38m 23s means "32 days, 7 hours, 38 minutes and 23 seconds".

This field is based on the StartTime property.

The Started at date/time tells you when the target server was started, relative to the computer on which Foxhound is running.

This field is based on the StartTime property.

SPs were OK: YYY, NNN or some combination of Ys and Ns indicates whether or not Foxhound had deployed, and was using, these three stored procedure on the target database when the Top Sample was recorded: rroad_connection_properties, rroad_database_properties and rroad_engine_properties.

These stored procedures are used by Foxhound to improve the performance of the sampling process, but they are not absolutely required. If the user id that Foxhound uses to connect to the target database doesn't have the RESOURCE authority then Foxhound won't be able to CREATE these procedures on the target database.

If SPs OK: isn't all Ys, try stopping and starting sampling to see if the Foxhound's inability to push these procedures to the target database was a transient condition. That won't affect the History display, just the gathering of future samples.

The Database file version: shows the version and build number of the SQL Anywhere software that was used to initialize the target database file, as recorded with the Top Sample.

For database files created with SQL Anywhere Version 9 and higher this field is based on the SYSHISTORY table. For database files created with earlier versions (5.5 through 8) Foxhound uses a proprietary process to determine the value to display. For early versions and for databases that have had the upgrade utility run on them this value may be somewhat imprecise.

The Cache was field tells you how much RAM the server was using for the database cache when the Top Sample was recorded, and how current cache size compared with the maximum.

These fields are based on the CurrentCacheSize and MaxCacheSize properties.

The Database file: field is the full file specification for the target database when the Top Sample was recorded.

This field is based on the File property.


4.3 Top Sample    [Top]

The Top Sample section shows the topmost successful sample, if there is one.

A "successful sample" is one that actually shows performance data rather than a message like "Database server not found".

The Top Sample section consists of 5 or 6 lines:

If the Age: interval grows very long without a new sample being displayed, and you are running an application that is sending a heavy workload to a target server on the network, and both Foxhound and the application are running on the same workstation, try running Foxhound and the test application on different workstations. In this scenario, Foxhound's connection to the target server may not be able to gather connection-level information on a timely basis. In some cases, it may not display the next sample until after the heavy workload is completely finished, and some of the rate calculations may be incorrect; e.g., commits per second, etc.

The rest of the color highlighting in this section is controlled by values in the Peaks section below it, as follows:

Dashes "-" are displayed for omitted column values instead of empty spaces. This makes it clear which values are not available or not applicable, and it also makes the resulting text somewhat easier to read when you use copy-and-paste. For example, the "CPU Time" percentage appears as a dash "-" for the first sample because it can only be calculated for second and later samples.

Note: This use of dashes "-" does not apply to columns which have been entirely omitted because the data is not available for the version of SQL Anywhere being used for the target database; e.g., the "CPU Time" column does not appear at all for version 5 and 6 target databases.

The Top Sample column shows the date/time that Foxhound recorded the topmost successful sample.

The Interval column shows the actual time interval between the previous sample and this one.

Foxhound tries to record a new sample every 10 seconds but the actual interval can vary. A very long interval like 1h 19m 48s may indicate the computer was in standby mode.

Latency...

Latency, also known as response time or access time, is a measure of how long it takes the the database to respond to a single request:

The Heartbeat and Sample Time numbers are calculated by Foxhound; they are not based on any builtin SQL Anywhere properties.

Although Heartbeat and Sample times are calculated to the millisecond (0.001 second), Foxhound doesn't show them with any more precision than one decimal place (0.1 second) because the underlying logic is no more precise than that. Sample times are simply rounded to the nearest tenth of a second.

However, Heartbeat times are often very small and would appear as zero if they were rounded to the nearest tenth of a second. Because it may be important to see the difference between zero and non-zero values, Heartbeat times are handled differently: zero values are shown as 0s and non-zero values are adjusted upwards to the nearest tenth of a second; i.e, the smallest non-zero value shown is 0.1s even if the calculated Heartbeat time is as small as 0.001 second.

The formula used is ROUND ( heartbeat_time_in_milliseconds + 49, -2 ).

Throughput...

Throughput, also known as bandwidth, is a measure of how many requests the database can respond to per unit of time:

These numbers are based on the Req, Commit, BytesReceived and BytesSent properties. The Commits column will be empty if connection details are not being recorded; see Foxhound Options - Connection Sampling Threshold.

The Conns column shows how many connections existed, with Foxhound itself counting as 1.

This number is based on the ConnCount property, and it may differ slightly from the number of connections shown in the connections detail section at the bottom of the page, because the ConnCount property and connection details are recorded at slightly different points in time.

The Executing, Idle, Waiting Conns columns show how many connections were executing, idle or waiting.

These numbers are based on the ReqStatus and RequestTiming properties, and they will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

Active Req, Max Req, Waiting Req:

A request is an atomic unit of work performed for a connection.

These numbers are based on the ActiveReq, MultiProgrammingLevel, Threads and UnschReq properties.

Locks Held, Conns Blocked:

These numbers are based on the LockCount and BlockedOn properties.

The CPU Time column shows three values:

The CPU Time values are for the target SQL Anywhere server as a whole, not an individual target database when the server is running more than one database. Also, the percentages are adjusted for the number CPUs being used by SQL Anywhere; i.e., if SQL Anywhere is using 25% of the processing resources of each and every one of four CPUs, the number will be shown as 25% rather than 100%. The time used is the total across all CPUs; it is not adjusted in the same manner.

These numbers are based on the following properties: NumLogicalProcessorsUsed, NumProcessorsAvail, NumProcessorsMax and ProcessCPU.

The Temp Space column shows the total amount of temporary space used by all the connections.

Temporary pages are used for many purposes, most often to hold intermediate results during query processing. Even if there is no temporary file, as with an in-memory no write database, temporary space is allocated and used by the engine.

This column is based on the PageSize and TempFilePages properties, and it will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

Cache Panics, Low Memory, Satisfaction:

These numbers are based on the CacheHits, CachePanics, CacheRead and QueryLowMemoryStrategy properties.

Checkpoint, Recovery Urgency:

These numbers are based on the CheckpointUrgency and RecoveryUrgency properties, and they are used by the target server to help decide when to take a checkpoint. They both increase monotonically until a checkpoint is taken, then drop to zero.

The Recovery Urgency may exceed 100% because SQL Anywhere enforces a lower boundary on the interval between successive checkpoints. This lower bound is calculated using the checkpoint_time and recovery_time options, and the default is 2 minutes. If Recovery Urgency increases rapidly immediately after one checkpoint is taken, it may continue far beyond 100% before the next checkpoint is allowed.

Checkpoints, Rollbacks:

These numbers are based on the Chkpt and Rlbk properties. The Rollbacks column will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

The DB File Frags column is the number of file fragments in the SYSTEM dbspace file.

This column is based on the DBFileFragments property.

Free Disk Space - Sys, Temp, Log, Other:

These numbers are based on the properties returned by the sa_disk_free_space procedure. The Log column will be empty for an in-memory database, and the Other column will be empty for any database that doesn't have any secondary database files.

Disk Reads, Writes:

These numbers are based on the DiskRead and DiskWrite properties.

The Log Writes column shows the number of pages that have been written to the transaction log, in the previous interval (top number +nn) and since the server started (nn).

This column is based on the LogWrite property.

Index Adds, Lookups, Satisfaction:

These numbers are based on the IndAdd, IndLookup and FullCompare properties.

Full Index Comps shows how many times additional information had to be obtained from the table data in order to satisfy an index lookup, in the previous interval (top number +nn) and since the server started (nn).

This number is based on the FullCompare property.


4.4 Peaks    [Top]

The Peaks section consists of a single line of peak values, where "peak" means "largest" for most values, and "smallest" for the Cache Satisfaction and Index Satisfaction percentages.

Not every column has a peak shown; e.g., there are no peaks recorded for the Free Disk Space columns.

The Peaks section on the History page looks the same as the Peaks section on the Monitor Database page. What you see in both places are the peak values as they were recorded when the page is displayed. For example, clicking on Reset Peaks on the Monitor Database page will affect what you see on the next History page display.

The Peaks section will disappear from the History page if you scroll back prior to the "Peaks since" timestamp. That's because the peaks don't have any meaning for samples recorded prior to the first peak being recorded.

Clicking on a link in the Peaks section will scroll the History page to that sample in the current browser window or tab, rather than opening a new window.

If a peak isn't shown as a hyperlink, the corresponding sample data may have been deleted by the background purge process. See the Foxhound Options page for more information on purging sample data.

Some peak values are displayed as rates (e.g., bytes per second nn/s) rather than counts or amounts like nnk.

The reason for this is that the interval between samples can vary, and a true comparison of "larger versus smaller" should take that into account. For example, a server that sent Bytes Out of 5M in an 8 second interval was actually busier than one that sent 6M in a 12 second interval (as far as Bytes Out was concerned).

Peak values are used to determine almost all of the color highlighting in the other sections (Top Sample and Recent Samples) above and below the Peaks section, as follows:

The Peaks since link identifies the earliest sample that was used to compute peak values.

This will be the first sample ever recorded for this database, or the first sample recorded after the most recent pressing of the button.

You can click on this link to open the History page in a separate browser window or tab, scrolled to this sample.

If the Peaks since timestamp isn't shown as a hyperlink, the corresponding sample data may have been deleted by the background purge process. See the Foxhound Options page for more information on purging sample data.

The Heartbeat, Sample Times peaks

The Heartbeat and Sample time numbers are calculated by Foxhound; they are not based on any builtin SQL Anywhere properties.

Although Heartbeat and Sample times are calculated to the millisecond (0.001 second), Foxhound doesn't show them with any more precision than one decimal place (0.1 second) because the underlying logic is no more precise than that. Sample times are simply rounded to the nearest tenth of a second.

However, Heartbeat times are often very small and would appear as zero if they were rounded to the nearest tenth of a second. Because it may be important to see the difference between zero and non-zero values, Heartbeat times are handled differently: zero values are shown as 0s and non-zero values are adjusted upwards to the nearest tenth of a second; i.e, the smallest non-zero value shown is 0.1s even if the calculated Heartbeat time is as small as 0.001 second.

The formula used is ROUND ( heartbeat_time_in_milliseconds + 49, -2 ).

The Req, Commits, Bytes peaks

These numbers are based on the Req, Commit BytesReceived and BytesSent properties.

The Conns peak shows the largest number of connections that existed.

This number is based on the ConnCount property.

The Executing, Idle, Waiting Conns peaks show the largest numbers of connections that were executing, idle or waiting.

These numbers are based on the ReqStatus and RequestTiming properties, and they will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

Active Req, Max Req, Waiting Req peaks:

A request is an atomic unit of work performed for a connection.

These numbers are based on the ActiveReq, MultiProgrammingLevel, Threads and UnschReq properties.

Locks Held, Conns Blocked peaks:

These numbers are based on the LockCount and BlockedOn properties.

The CPU Time peak shows the largest percentage of CPU time used during a single interval.

The CPU Time peak is for the target SQL Anywhere server as a whole, not an individual target database when the server is running more than one database. Also, the percentage is adjusted for the number CPUs being used by SQL Anywhere; i.e., if SQL Anywhere is using 25% of the processing resources of each and every one of four CPUs, the number will be shown as 25% rather than 100%.

This number is based on the following properties: NumLogicalProcessorsUsed, NumProcessorsAvail, NumProcessorsMax and ProcessCPU.

The Temp Space peak shows the largest amount of temporary space used by all the connections.

Temporary pages are used for many purposes, most often to hold intermediate results during query processing. Even if there is no temporary file, as with an in-memory no write database, temporary space is allocated and used by the engine.

This column is based on the PageSize and TempFilePages properties, and it will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

Cache Panics, Low Memory, Satisfaction peaks:

These numbers are based on the CacheHits, CachePanics, CacheRead and QueryLowMemoryStrategy properties.

Checkpoint, Recovery Urgency peaks:

These numbers are based on the CheckpointUrgency and RecoveryUrgency properties, and they are used by the target server to help decide when to take a checkpoint. They both increase monotonically until a checkpoint is taken, then drop to zero.

The Recovery Urgency may exceed 100% because SQL Anywhere enforces a lower boundary on the interval between successive checkpoints. This lower bound is calculated using the checkpoint_time and recovery_time options, and the default is 2 minutes. If Recovery Urgency increases rapidly immediately after one checkpoint is taken, it may continue far beyond 100% before the next checkpoint is allowed.

Checkpoints, Rollbacks peaks:

These numbers are based on the Chkpt and Rlbk properties.

The Rollbacks column will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

The DB File Frags peak is the largest number of file fragments in the SYSTEM dbspace file.

This column is based on the DBFileFragments property.

Disk Reads, Writes peaks:

These numbers are based on the DiskRead and DiskWrite properties.

The Log Writes peak shows the highest rate at which pages that have been written to the transaction log.

This column is based on the LogWrite property.

Index Adds, Lookups, Satisfaction peaks:

These numbers are based on the IndAdd, IndLookup and FullCompare properties.

Full Index Comps shows the highest rate at which additional information had to be obtained from the table data in order to satisfy an index lookup.

This number is based on the FullCompare property.


4.5 Samples    [Top]

The Samples section on the History page looks the same as the Recent Samples section on the Monitor Database page, except that 100 samples are displayed instead of 10.

Alert and All Clear messages also appear in this section, as well as messages that tell you when sampling was not successful; e.g., "Database server not found" and "Foxhound stopped".

The color highlighting in this section is controlled by values in the Peaks section above it, as follows:

The Samples column shows the date/time that Foxhound recorded each sample.

You can click on these links to scroll the associated sample to the top of the page.

The pair of numbers [in square brackets] above the "Samples" column title are the Foxhound database primary key values sampling_id and sample_set_number for the top sample shown on this page; e.g., [4,1796]. These key values are helpful when running adhoc queries on the Foxhound database.

The Interval column shows the actual time interval between the previous sample and this one.

Foxhound tries to record a new sample every 10 seconds but the actual interval can vary. A very long interval like 1h 19m 48s may indicate the computer was in standby mode.

Latency...

Latency, also known as response time or access time, is a measure of how long it takes the the database to respond to a single request:

The Heartbeat and Sample time numbers are calculated by Foxhound; they are not based on any builtin SQL Anywhere properties.

Although Heartbeat and Sample times are calculated to the millisecond (0.001 second), Foxhound doesn't show them with any more precision than one decimal place (0.1 second) because the underlying logic is no more precise than that. Sample times are simply rounded to the nearest tenth of a second.

However, Heartbeat times are often very small and would appear as zero if they were rounded to the nearest tenth of a second. Because it may be important to see the difference between zero and non-zero values, Heartbeat times are handled differently: zero values are shown as 0s and non-zero values are adjusted upwards to the nearest tenth of a second; i.e, the smallest non-zero value shown is 0.1s even if the calculated Heartbeat time is as small as 0.001 second.

The formula used is ROUND ( heartbeat_time_in_milliseconds + 49, -2 ).

Throughput...

Throughput, also known as bandwidth, is a measure of how many requests the database can respond to per unit of time:

These numbers are based on the Req, Commit, BytesReceived and BytesSent properties. The Commits column will be empty if connection details are not being recorded; see Foxhound Options - Connection Sampling Threshold.

The Conns column shows how many connections existed, with Foxhound itself counting as 1.

This number is based on the ConnCount property, and it may differ slightly from the number of connections shown in the connections detail section at the bottom of the page, because the ConnCount property and connection details are recorded at slightly different points in time.

The Executing, Idle, Waiting Conns columns show how many connections were executing, idle or waiting.

These numbers are based on the ReqStatus and RequestTiming properties, and they will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

Active Req, Max Req, Waiting Req:

A request is an atomic unit of work performed for a connection.

These numbers are based on the ActiveReq, MultiProgrammingLevel, Threads and UnschReq properties.

Locks Held, Conns Blocked:

These numbers are based on the LockCount and BlockedOn properties.

The CPU Time column shows the percentage of CPU time used during the preceding interval.

The CPU Time is for the target SQL Anywhere server as a whole, not an individual target database when the server is running more than one database. Also, the percentage is adjusted for the number CPUs being used by SQL Anywhere; i.e., if SQL Anywhere is using 25% of the processing resources of each and every one of four CPUs, the number will be shown as 25% rather than 100%.

This number is based on the following properties: NumLogicalProcessorsUsed, NumProcessorsAvail, NumProcessorsMax and ProcessCPU.

The Temp Space column shows the total amount of temporary file space used by all the connections.

Temporary pages are used for many purposes, most often to hold intermediate results during query processing. Even if there is no temporary file, as with an in-memory no write database, temporary space is allocated and used by the engine.

This column is based on the PageSize and TempFilePages properties, and it will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

Cache Panics, Low Memory, Satisfaction:

These numbers are based on the CacheHits, CachePanics, CacheRead and QueryLowMemoryStrategy properties.

Checkpoint, Recovery Urgency:

These numbers are based on the CheckpointUrgency and RecoveryUrgency properties, and they are used by the target server to help decide when to take a checkpoint. They both increase monotonically until a checkpoint is taken, then drop to zero.

The Recovery Urgency may exceed 100% because SQL Anywhere enforces a lower boundary on the interval between successive checkpoints. This lower bound is calculated using the checkpoint_time and recovery_time options, and the default is 2 minutes. If Recovery Urgency increases rapidly immediately after one checkpoint is taken, it may continue far beyond 100% before the next checkpoint is allowed.

Checkpoints, Rollbacks:

These numbers are based on the Chkpt and Rlbk properties.

The Rollbacks column will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

The DB File Frags column is the number of file fragments in the SYSTEM dbspace file.

This column is based on the DBFileFragments property.

Free Disk Space - Sys, Temp, Log, Other:

These numbers are based on the properties returned by the sa_disk_free_space procedure.

The Log column will be empty for an in-memory database, and the Other column will be empty for any database that doesn't have any secondary database files.

Disk Reads, Writes:

These numbers are based on the DiskRead and DiskWrite properties.

The Log Writes column shows the rate at which pages were written to the transaction log in the previous interval.

This column is based on the LogWrite property.

Index Adds, Lookups, Satisfaction:

These numbers are based on the IndAdd, IndLookup and FullCompare properties.

Full Index Comps shows the rate at which additional information had to be obtained from the table data in order to satisfy an index lookup, in the previous interval.

This number is based on the FullCompare property.


4.6 Blocked Connections    [Top]

The Blocked Connection section displays blocked connections as they existed when the Top Sample was recorded. This section looks the same as the Blocked Connections section on the Monitor Database page, except

This section will be empty if no blocked connections existed when the Top Sample was recorded, or if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

The Blocked Statement column contains the SQL statement the blocked connection was trying to execute.

This column is based on the LastStatement property.

The Waiting Time is the length of time the blocked connection has been waiting for the blocked statement to execute.

This number is based on the LastReqTime property.

The greyed-out arrow to the left of the Waiting Time column title indicates that entries in this section are sorted in decreasing order by the Waiting Time column, and that this choice of sort order is fixed.

The Reason... column describes what kinds of locks are causing the block.

This value is based on columns returned by sa_locks.

The Locked Row Query... is a SELECT statement you can copy and paste into dbisql to find the row in the target database that is locked.

This column is based on the LockName property and the sa_locks.row_identifier column.

The Blocked Connection... columns identify the connection that is blocked by a lock:

These columns are based on the Userid, Number, NodeAddress and Name properties.

The Blocked by... columns identify the connection that is holding the lock causing the block:

These columns are based on the Userid, Number, NodeAddress and Name properties.

The Blocked by Transaction Running Time is the length of time a transaction has been running on the blocking connection.

This number is based on the TransactionStartTime property.


4.7 Connections    [Top]

The Connections section shows connections as they existed when the Top Sample was recorded. This section looks the same as the Connections section on the Monitor Database page, except

This section will be empty if connection details are not being recorded; see Foxhound Options - Connection sampling threshold.

The up or down arrow to the left of a single column title indicates that entries in this section are sorted in ascending or decreasing order by that column. Click on that column title to change the direction of that sort (ascending to or from descending), or click on a different column title to sort the entries by that column.

The tie-breaker sort column is Conn #; if multiple entries in this section have the same value in the selected sort column, those entries are sorted in ascending order by Connection Number.

Note: If you add up the connection-level figures like "Req" you might not get the same number as shown in the server-level "Req" column.

That's because the connection-level and server-level statistics are recorded at slightly different times, and one value might lag behind the other.

The Conn # / User / IP / Name columns identify each connection:

These columns are based on the Number, Userid, NodeAddress and Name properties.

The Req column shows how many times the server has started processing a new request or resumed processing an existing request for this connection since it started.

A request is an atomic unit of work performed for a connection.

This number is based on the Req property.

Time Since Last Request is the elapsed time since the last time a request was started for this connection.

This number is based on the LastReqTime property.

The Current Req Status shows whether this connection was Idle, Waiting for thread, Waiting for I/O, Waiting for shared resource, Blocked by lock or Executing.

This column is based on the ReqStatus property.

The Blocked by Conn # column shows the connection number of the connection that is blocking this one.

This column is based on the BlockedOn property.

Transaction Running Time is the length of time a transaction has been running on this connection.

This number is based on the TransactionStartTime property.

Locks Held, Conns Blocked:

These columns are based on the LockCount and BlockedOn properties.

CPU % / Time:

These numbers are based on the following properties: NumLogicalProcessorsUsed, NumProcessorsAvail, NumProcessorsMax and ApproximateCPUTime.

Temp Space, Rollback Log, Uncommitted:

These numbers are based on the PageSize, TempFilePages, RollbackLogPages and UncommitOp properties.

Low Memory, Cache Satisfaction:

These numbers are based on the QueryLowMemoryStrategy, CacheHits and CacheRead properties.

Time Connected is the elapsed time since this connection was established.

This number is based on the LoginTime property.

The Total Waits, Waiting Time columns show how many times and for how long this connection has been blocked or forced to wait.

These numbers are based on the following properties: ReqCountBlockContention, ReqCountBlockIO, ReqCountBlockLock, ReqCountUnscheduled, ReqTimeBlockContention, ReqTimeBlockIO, ReqTimeBlockLock and ReqTimeUnscheduled.

For more information see this Q&A entry:
How do I get something to show up in the Total Waits, Waiting Time columns?

Isolation Level shows the current isolation level for this connection. Note that a connection can change the isolation level dynamically, for any particular query and even for part of a query.

This column is based on the IsolationLevel property.

Client Requests, Time:

These numbers are based on the RequestsReceived and ReqTimeActive properties.

Total, Current Prepares:

These numbers are based on the Prepares and PrepStmt properties.

Commits, Rollbacks are the total numbers of commit and rollback requests that have been handled by the server for this connection since it started.

These numbers are based on the Commit and Rlbk properties.

Disk Reads, Writes

These numbers are based on the DiskRead and DiskWrite properties.

Log Writes is the total number of pages that have been written to the transaction log for this connection since it started.

This number is based on the LogWrite property.

Index Adds, Lookups, Satisfaction:

These numbers are based on the IndAdd, IndLookup and FullCompare properties.

Full Index Comps shows how many times additional information had to be obtained from the table data in order to satisfy an index lookup, for this connection since it started.

This number is based on the FullCompare property.

Bytes In / Out:

These numbers are based on the BytesReceived and BytesSent properties.

The Last Statement: line displays last SQL statement this connection was executing.

This line only appears for connections where the LastStatement property contains a value. For more information see this Q&A entry:
How do I get something to show up in the Last Statement column?

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