How to identify network issues in PCoIP Logs

Rate this Article
Average: 1 (1 vote)

All HP Anyware PCoIP Agents, PCoIP Zero Clients, PCoIP Remote Workstation Cards and PCoIP Software Clients log network statistics in the logs. The statistics are logged at different detail levels on different products. Understanding how to read these log file entries can assist in troubleshooting potential network issues impacting a users experience. For a visual representation of the network statistics, use the PCoIP Software Statistics Viewer.

HP Anyware Agents

Both the Linux and Windows agent generate the same logging information for network statistics. All network statistics are store in the PCoIP server logs

Latency

Latency information is published in the logs every 60 seconds and the statistics apply to the last 60 seconds. 

LVL:2 RC: 0 MGMT_PCOIP_DATA :Tx thread info: round trip time (ms) = 1, variance = 0, rto = 101, last = 2, max = 10

Round trip time

Round trip time is the average number of milliseconds taken in the last 60 seconds for the PCoIP data to be transmitted to the client and receipt of the client response. The ping is done over HP Anyware PCoIP UDP 4172 communication and does not use ICMP data. This is important to note as when ping is used an ICMP Echo packet is sent to the other computer and an ICMP Echo Reply is sent back. If the round trip time is significantly different to the time ping reports, there maybe QoS running on the network. By default QoS places UDP at the lowest priority while ICMP is placed at a higher priority and there will be a difference in time when there is congestion on the network.

Variance

The variance is the milliseconds of deviation of the individual round trip times in the last 60 seconds. This number should be close to 0. Once this number starts to climb it indicates packets are getting buffered between the host and client. The larger this number the greater the jitter which leads to a poor user experience.

Last

Last is the last round trip time recorded, measured in milliseconds.

Max

Max is the highest round trip time in milliseconds in the last 60 seconds.

Bandwidth

Bandwidth statistics are published in the logs every 60 seconds and apply to the last 60 seconds.

LVL:2 RC: 0 MGMT_PCOIP_DATA :Tx thread info: bw limit = 142502, avg tx = 183.5, avg rx = 40.4 (kbit/s)

bw limit

Bandwidth limit is the maximum bandwidth at which PCoIP will transmit at. The limit is the current limit at that point in time and is displayed in kbit/s. This limit is dynamically adjusted based on current network connections but can be limited to a maximum by setting the maximum PCoIP session bandwidth (LINK TO KB)  and a minimum by setting the PCoIP session bandwidth floor (LINK TO KB). A low bandwidth limit can be due to:

  • PCoIP settings limiting the bandwidth
  • The session has not required more bandwidth yet
  • Packet Loss
  • High latency

avg tx

Average transmit bandwidth is an average of the last 60 seconds of the transmitted data speeds in kbit/s. As this log is collected from the PCoIP Agent this is transmission from the Agent to Client.

Note: PCoIP transmission bursts frequently depending on how many pixels are changing per a second. As this is an average it will not accurately reflect host large a burst can be.

avg rx

Average receive bandwidth is an average of the last 60 seconds of the receive data speeds in kbit/s. As this log is collected from the PCoIP Agent this is transmission from the Client to Agent.

Note: PCoIP transmission bursts frequently depending on how many pixels are changing per a second. As this is an average it will not accurately reflect how large a burst of data can be.

Packet Loss

Packet loss statistics are published in the logs every 60 seconds and apply to the last 60 seconds. Troubleshooting PCoIP packet loss on the LAN and WAN networks?

LVL:1 RC: 0 VGMAC :Stat frms: R=000000/000000/296923 T=022209/380982/107934 (A/I/O) Loss=0.00%/0.00% (R/T)

Loss

Packet loss is the % of packets lost in the last 60 seconds. As this is the PCoIP Agent logs, the left hand side reflects packets lost between the HP Anyware Client and PCoIP Agent and the right hand side reflects packets lost between the PCoIP Agent and the HP Anyware Client. Loss is recommended to be less than 0.1%. The greater the loss the more impact on the user experience. PCoIP is a real time protocol. If packet loss occurs, the missing data is retransmitted at the discretion of the protocol. If it was packet of audio, it would not get retransmitted as the time has already passed for the user to hear the audio. To much packet loss and you would hear silence, pops, squeaks and other audio artifacts. 

Decrease (Loss)

When there is network loss you will see this in the logs. This shows 

LVL:1 RC: 0 MGMT_PCOIP_DATA :ubs-BW-decr: Decrease (loss) loss=0.014 current[kbit/s]=7315.3338, active[kbit/s]=7100.0913 -> 6353.0162, adjust factor=13.15%, floor[kbit/s]=104.0000

Loss

The number of packets lost recently triggering the bandwidth adjustment. In this example 14 packets were lost.

Current

The current kbit/s is the current PCoIP transmission rate. In this example this log entry was taken from the PCoIP Agent therefore, this is the PCoIP Agent to client transmission rate.

Active 

The PCoIP bandwidth limit covered above, is the current limit that PCoIP can transmit at. The first number after active was the previous bandwidth limit before the packet loss event and the second number is the bandwidth limit after adjustment. The larger the packet loss event the greater the adjustment. 

Adjust factor

The adjust factor shows the percentage of change from the current bandwidth utilization to the new bandwidth limit. In this example the session was actively using 7315.3338 kbit/s and now has a limit of 6353.0162 kbit/s. The PCoIP session now has 13.15% less bandwidth available than it was utilizing and now has to dynamically adjust initial image quality and frame rate to fit inside the new bandwidth limit.

Floor

This is the session floor and represents the minimum value PCoIP can adjust the bandwidth limit to.

Decrease (Latency) or Decrease (High Latency)

These messages are only visible in Level 3 logging. Refer to How do I set the verbosity level for PCoIP Agent log entries? for information on how to change the logging level.

When experiencing spikes in latency, the PCoIP session will reduce the bandwidth limit. The spikes in latency can be network related or software/operating system related.

LVL:3 RC: 0 MGMT_PCOIP_DATA :BW: Decrease (latency) loss 0.000 active[kbit/s] 2051.9719 -> 1025.9859, tx/rx rate[kbit/s] 1029.7648 / 872 floor[kbit/s] 104.0000 cons 128

LVL:3 RC: 0 MGMT_PCOIP_DATA :BW: Decrease (high latency) loss 0.000 active[kbit/s] 205.0407 -> 104.0000, tx/rx rate[kbit/s] 1644.0269 / 2768 floor[kbit/s] 104.0000 cons 0

Active 

The PCoIP bandwidth limit covered above, is the current limit that PCoIP can transmit at. The first number after active was the previous bandwidth limit before the packet loss event and the second number is the bandwidth limit after adjustment. The larger the packet loss event the greater the adjustment. 

Decrease (overrun)

These messages are only visible in Level 3 logging. Refer to How do I set the verbosity level for PCoIP Agent log entries? for information on how to change the logging level.

LVL:3 RC: 0 MGMT_PCOIP_DATA :BW: Decrease (overrun) loss 0.000 active[kbit/s] 30518.4345 -> 15259.2173, tx/rx rate[kbit/s] 2189.0103 / 1016 floor[kbit/s] 104.0000 cons 131

This message indicates that the server was transmitting at a higher rate than the client can receive, possibly due to a constrained network environment.  

Decrease (floor) 

MGMT_PCOIP_DATA  :BW: Decrease (floor) old = 207.2000 new = 145.0400, tx = 299.5441, avg=155

The Decrease (floor) message indicates a more severe case than the Decrease (overrun).

Refer following session planning guide to tune your network for PCoIP

http://www.teradici.com/web-help/pcoip_session_planning/current/

FAQ

How long after a Decrease does it take for the bandwidth estimation to start increasing again? 

If there has been no reason to decrease the estimated bandwidth available for 100ms, then PCoIP will start to increase the amount of estimated bandwidth available.