Get a specified milestone timer value for the current transaction.


#include <ts/ts.h>

TSReturnCode TSHttpTxnMilestoneGet(TSHttpTxn txnp, TSMilestonesType milestone, TSHRTime * time)


TSHttpTxnMilestoneGet() will fetch a specific milestone timer value for the transaction txnp. These timers are calculated during the lifetime of a transaction and are measured in nanoseconds from the beginning of the transaction. time is used a pointer to storage to update if the call is successful.

Value Milestone
TS_MILESTONE_SM_START Transaction state machine is initialized.
TS_MILESTONE_UA_BEGIN The client connection is accepted.
TS_MILESTONE_PLUGIN_ACTIVE Amount of time plugins were active plus start time.
TS_MILESTONE_PLUGIN_TOTAL Wall time while plugins were active plus start time.
TS_MILESTONE_UA_READ_HEADER_DONE The request header from the client has been read and parsed.
TS_MILESTONE_CACHE_OPEN_READ_BEGIN Initiate read of the cache.
TS_MILESTONE_CACHE_OPEN_READ_END Initial cache read has resolved.
TS_MILESTONE_CACHE_OPEN_WRITE_BEGIN Start open for cache write.
TS_MILESTONE_CACHE_OPEN_WRITE_END Cache has been opened for write.
TS_MILESTONE_DNS_LOOKUP_BEGIN Initiate host resolution in HostDB
TS_MILESTONE_DNS_LOOKUP_END Host resolution resolves.
TS_MILESTONE_SERVER_FIRST_CONNECT First time origin server connect attempted or shared shared session attached.
TS_MILESTONE_SERVER_CONNECT Most recent time origin server connect attempted or shared session attached.
TS_MILESTONE_SERVER_CONNECT_END More recent time a connection attempt was resolved.
TS_MILESTONE_SERVER_BEGIN_WRITE First byte is written to the origin server connection.
TS_MILESTONE_SERVER_FIRST_READ First byte is read from connection to origin server.
TS_MILESTONE_SERVER_READ_HEADER_DONE Origin server response has been read and parsed.
TS_MILESTONE_UA_BEGIN_WRITE The response header write to the client starts.
TS_MILESTONE_SERVER_CLOSE Last I/O activity on origin server connection.
TS_MILESTONE_UA_CLOSE Last I/O activity on the client socket, or connection abort.
TS_MILESTONE_SM_FINISH Transaction has finished, state machine final logging has started.
  • The server connect times predate the transmission of the SYN packet. That is, before a connection to the origin server is completed.

  • A connection attempt is resolved when no more connection related activity remains to be done, and the connection is either established or has failed.

  • TS_MILESTONE_UA_CLOSE and TS_MILESTONE_SERVER_CLOSE are updated continuously during the life of the transaction, every time there is I/O activity. The updating stops when the corresponding connection is closed, leaving the last I/O time as the final value.

  • The cache OPEN milestones time only the initial setup, the open, not the full read or write.

  • TS_MILESTONE_PLUGIN_ACTIVE and TS_MILESTONE_PLUGIN_TOTAL are different from the other milestones as they measure elapsed time, not event time. The value is the elapsed time plus TS_MILESTONE_SM_START. This was decided to be more convenient because then these milestones can be handled / displayed in the same way as the other milestones, as offsets from TS_MILESTONE_SM_START.

    TS_MILESTONE_PLUGIN_ACTIVE value is the amount of time the plugin was active, that is performing computation. TS_MILESTONE_PLUGIN_TOTAL is the wall time which includes any time the transaction was blocked while a plugin was active. For instance if a plugin waits on an external event, that waiting time will be in TS_MILESTONE_PLUGIN_TOTAL but not in TS_MILESTONE_PLUGIN_ACTIVE.

Return Values

TS_SUCCESS if successful and time was updated, otherwise TS_ERROR.

See Also