[Spice-devel] [PATCH 2/2] manual: Add section about debugging

[Christophe Fergeau]

This details the basics for now, but can be detailed in the future.
---
 docs/manual/manual.txt | 51 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)

diff --git a/docs/manual/manual.txt b/docs/manual/manual.txt
index a66554a..531b0e4 100644
--- a/docs/manual/manual.txt
+++ b/docs/manual/manual.txt
@@ -1082,6 +1082,57 @@ You should now be able to access the qemu-system-x86_64 Spice binary.
 
 :numbered!:
 
+Debugging
+=========
+
+Server-side
+-----------
+
+If the virtual machine was started using QEMU directly, SPICE server logs will be output to
+your console standard input.
+When using libvirt, logs are available from `/var/log/libvirt/qemu/` for `qemu:///system`, and
+from to `~/.cache/libvirt/qemu/log` for `qemu:///session`.
+
+Client-side
+-----------
+
+remote-viewer can be started with `SPICE_DEBUG=1` in the environment, or with
+`--spice-debug` in order to get it to output more logs on stdout.
+
+Guest-side
+----------
+
+QXL
+~~~
+
+On recent Linux kernels using the QXL kms driver, booting the kernel with the
+`drm.debug=0xf` parameter.  `journalctl -k`/`dmesg` will then contain debug
+logs for the QXL kms driver. This can also be changed at runtime by echo'ing
+this value to `/sys/module/drm/parameters/debug`.
+
+Agent
+~~~~~
+
+On Linux, `journalctl -t spice-vdagentd -t spice-vdagent` will display the agent log messages.
+spice-vdagent can also be restarted by hand with the `-d` argument in order to display more logs.
+
+Recording/replaying SPICE server traffic
+----------------------------------------
+
+Since spice-server 0.12.6, it's possible to record display traffic sent by the
+SPICE server in order to replay it afterwards for a client without needing to
+start a VM. This is achieved by setting the environment variable
+`SPICE_WORKER_RECORD_FILENAME` to the filename to write the traffic to before starting
+QEMU.
+
+Once the recording session is done, the `spice-server-replay` tool can be used
+to replay the previously recorded SPICE session, for example:
+
+-------------------------------------------------
+spice-server-replay -p 5900 -c "remote-viewer spice://localhost:5900" recorded-session.spice
+-------------------------------------------------
+
+
 [appendix]
 Manual authors
 ==============
-- 
2.5.0