public class PERF extends Protocol
Protocol.down(org.jgroups.Event)
, a header is added to the
message with the ID of the PERF protocol and the start time is set in the header.
On Protocol.up(org.jgroups.Event)
, the time difference is computed and a rolling average is updated in PERF.
Note that we can have several measurements by inserting PERF protocols with different IDs (Protocol.id) into the stack.
If PERF is used to measure latency between nodes running on different physical boxes, it is important that the clocks
are synchronized, or else latency cannot be computed correctly (may even be negative).Modifier and Type | Class and Description |
---|---|
protected static class |
PERF.PerfHeader |
Modifier and Type | Field and Description |
---|---|
protected Average |
avg |
protected int |
avg_size |
protected Address |
local_addr |
after_creation_hook, down_prot, ergonomics, id, log, stack, stats, up_prot
Constructor and Description |
---|
PERF() |
Modifier and Type | Method and Description |
---|---|
Object |
down(Event evt)
An event is to be sent down the stack.
|
Object |
down(Message msg)
A message is sent down the stack.
|
void |
init()
Called after instance has been created (null constructor) and before protocol is started.
|
double |
latencyInMs() |
double |
latencyInNs() |
void |
resetStats() |
Object |
up(Message msg)
A single message was received.
|
void |
up(MessageBatch batch)
Sends up a multiple messages in a
MessageBatch . |
accept, afterCreationHook, destroy, enableStats, getConfigurableObjects, getDownProtocol, getDownServices, getId, getIdsAbove, getLevel, getLog, getName, getProtocolStack, getSocketFactory, getThreadFactory, getTransport, getUpProtocol, getUpServices, getValue, isErgonomics, level, parse, providedDownServices, providedUpServices, requiredDownServices, requiredUpServices, resetStatistics, setDownProtocol, setErgonomics, setId, setLevel, setProperties, setProtocolStack, setSocketFactory, setUpProtocol, setValue, start, statsEnabled, stop, up
protected Average avg
protected Address local_addr
protected int avg_size
public double latencyInNs()
public double latencyInMs()
public void init() throws Exception
Protocol
public void resetStats()
resetStats
in class Protocol
public Object down(Event evt)
Protocol
down_prot.down()
.public Object down(Message msg)
Protocol
public Object up(Message msg)
Protocol
public void up(MessageBatch batch)
Protocol
MessageBatch
. The sender of the batch is always the same, and so is the
destination (null == multicast messages). Messages in a batch can be OOB messages, regular messages, or mixed
messages, although the transport itself will create initial MessageBatches that contain only either OOB or
regular messages.
The default processing below sends messages up the stack individually, based on a matching criteria
(calling Protocol.accept(org.jgroups.Message)
), and - if true - calls Protocol.up(org.jgroups.Event)
for that message and removes the message. If the batch is not empty, it is passed up, or else it is dropped.
Subclasses should check if there are any messages destined for them (e.g. using
MessageBatch.getMatchingMessages(short,boolean)
), then possibly remove and process them and finally pass
the batch up to the next protocol. Protocols can also modify messages in place, e.g. ENCRYPT could decrypt all
encrypted messages in the batch, not remove them, and pass the batch up when done.Copyright © 2018 JBoss, a division of Red Hat. All rights reserved.