Request log format

HTTP request logs are written by synapse (see for details).

See the following for how to decode the dense data available from the default logging configuration.

2020-10-01 12:00:00,000 - synapse.access.http.8008 - 311 - INFO - PUT-1000- - 8008 - {} Processed request: 0.100sec/-0.000sec (0.000sec, 0.000sec) (0.001sec/0.090sec/3) 11B !200 "PUT /_matrix/federation/v1/send/1600000000000 HTTP/1.1" "Synapse/1.20.1" [0 dbevts]
AAAATimestamp request was logged (not recieved)
BBBBLogger name (synapse.access.(http\|https).<tag>, where 'tag' is defined in the listeners config section, normally the port)
CCCCLine number in code
DDDDLog Level
EEEERequest Identifier (This identifier is shared by related log lines)
FFFFSource IP (Or X-Forwarded-For if enabled)
GGGGServer Port
HHHHFederated Server or Local User making request (blank if unauthenticated or not supplied)
IIIITotal Time to process the request
JJJJTime to send response over network once generated (this may be negative if the socket is closed before the response is generated)
KKKKUserland CPU time
LLLLSystem CPU time
MMMMTotal time waiting for a free DB connection from the pool across all parallel DB work from this request
NNNNTotal time waiting for response to DB queries across all parallel DB work from this request
OOOOCount of DB transactions performed
PPPPResponse body size
QQQQResponse status code
Suffixed with ! if the socket was closed before the response was generated.
A 499! status code indicates that Synapse also cancelled request processing after the socket was closed.
TTTTEvents fetched from DB to service this request (note that this does not include events fetched from the cache)

MMMM / NNNN can be greater than IIII if there are multiple slow database queries running in parallel.

Some actions can result in multiple identical http requests, which will return the same data, but only the first request will report time/transactions in KKKK/LLLL/MMMM/NNNN/OOOO - the others will be awaiting the first query to return a response and will simultaneously return with the first request, but with very small processing times.