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Python pygame Client/Server runs slow

I found a basic space invaders pygame on Youtube and I want to modify it in order that, as of right now, the server is doing all the processing and drawing, and the client only sends keyboard input(all run on localhost). The problem is that the game is no longer that responsive after I implemented this mechanism. It appears to be about 1 second delay after I press a key to when the ship is actually moving (when starting the game from pycharm, when it starts from cmd it's much worse).
I don't have any idea why this is happening because there isn't really anything heavy to process and I could really use your help.
I also monitored the Ethernet traffic in wireshark and there seems to be sent about 60-70 packets each second.
Here is the github link with all the necesary things: https://github.com/PaaulFarcas/C-S-Game

I would expect this code in the main loop is the issue:
recv = conn.recv(661)
keys = pickle.loads(recv)
The socket function conn.recv() will block until 661 bytes are received, or there is some socket event (like being closed). So your program is blocking every iteration of the main loop waiting for the data to arrive.
You could try using socket.setblocking( False ) as per the manual.
However I prefer to use the select module (manual link), as I like the better level of control it gives. Basically you can use it to know if any data has arrived on the socket (or if there's an error). This gives you a simple select-read-buffer type logic loop:
procedure receiveSocketData
Use select on the socket, with an immediate timeout.
Did select indicate any data arrived on my socket?
Read the data, appending it to a Rx-buffer
Does the Rx-buffer contain enough for a whole packet?
take the packet-chunk from the head of the Rx-buffer
decode & return it
Else
Keep the Rx-Buffer somewhere safe
return None
Did any errors happen on my socket
clear Rx-Buffer
close socket
return error
I guess using an unknown-sized packet, you could try to un-pickle it, and return OK when successful... this is quite inefficient though. I would use a fixed size packet and the struct module to pack and unpack it in network-byte-order.

Significant Delay in Receiving Data using Python Select()

I have a Python script that is used to receive data associated with a radio station audio event (such as a song or commercial) from the machine playing the audio. The script will parse and process the data and then send portions of it to various other destinations.
First the socket is set up:
client_socket_1 = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
print 'trying to open socket 1'
client_socket_1.connect((TCP_RCV_IP_CR1, TCP_RCV_PORT_CR1))
client_socket_1.setblocking(0)
except socket.error, e:
print 'Error', e, TCP_RCV_IP_CR1, '\n\n\n'
else:
SOCK1 = 1
print 'Successful connection to ',TCP_RCV_IP_CR1,'\n'
Now we wait until data is available to be read. I used select() and when the socket is ready to be read, the thread that parses and processes the data is spawned.
ready_1 = select.select([client_socket_1], [], [], 1) # select tells us when data is available at the socket
if ready_1[0] and SOCK1: # Don't run this code if there is no connection on client_socket_1 or no data available
t1 = Thread(target=processdata1) # Set up the thread
t1.start() # Call the process to process available data as a thread
It is important that the data be read as quickly as possible as it will be transported via TCP or UDP (depending on the particular data chunks and program specifications) along with the associated audio, and the function of one of the data items we are handling can create an on-air 'hiccup' in the audio if not received in a timely fashion. (TMI: It causes a 'replacement' commercial to play at the receiving end which is supposed to 'cover' the commercial audio we are sending. If the replacement spot doesn't start quickly enough listeners will hear the beginning of the commercial we are sending, then the local replacement one will start when our data is received and it sounds like a hiccup on the air.)
To confirm that my script is not always receiving the data quickly enough I telnetted to the port it is listening to and watched the data as it is received in the telnet window, then look at the Python output (which sends received data to stdout as soon as it is received) and I see about a 1.5-second delay between the telnet output and the Python output. This is the same amount of delay we have observed in normal on-air operation.
I chose to use select() because I was asked to multi-thread the script and I thought that would be a good way to know when to trigger a data-processing thread. My original idea was to simply loop through attempting to read data from each of the three systems we are monitoring and, when data is found, process it.
The thought was that if data is being processed from one system when another system has data ready to be read, it might cause a delay in processing and sending out the data from that machine. However, I can't see that delay being as significant as what I am experiencing now. I am considering going back to the original plan.
I would rather stick with what I have which is working flawlessly as long as data is received in a timely fashion. Any thoughts on why the excessively long delay?

I think it has to do with your timeout parameter in combination with the wlist and xlist parameters
Consider this piece of code
write_list = []
exception_list = []
select.select([client_socket_1], write_list, exception_list)
It takes an optional timeout parameter, like you use it. The documentation says
select() also takes an optional fourth parameter which is the number
of seconds to wait before breaking off monitoring if no channels have
become active. Using a timeout value lets a main program call select()
as part of a larger processing loop, taking other actions in between
checking for network input.
It might be that the call will always wait one second before returning because of the empty lists. Try
ready_1 = select.select(
[client_socket_1],
[client_socket_1],
[client_socket_1], 1
)
Or you can use a timeout value of 0, which
specifies a poll and never blocks.

What is the most efficient way to run independent processes from the same application in Python

I have a script that in the end executes two functions. It polls for data on a time interval (runs as daemon - and this data is retrieved from a shell command run on the local system) and, once it receives this data will: 1.) function 1 - first write this data to a log file, and 2.) function 2 - observe the data and then send an email IF that data meets certain criteria.
The logging will happen every time, but the alert may not. The issue is, in cases that an alert needs to be sent, if that email connection stalls or takes a lengthy amount of time to connect to the server, it obviously causes the next polling of the data to stall (for an undisclosed amount of time, depending on the server), and in my case it is very important that the polling interval remains consistent (for analytics purposes).
What is the most efficient way, if any, to keep the email process working independently of the logging process while still operating within the same application and depending on the same data? I was considering creating a separate thread for the mailer, but that kind of seems like overkill in this case.
I'd rather not set a short timeout on the email connection, because I want to give the process some chance to connect to the server, while still allowing the logging to be written consistently on the given interval. Some code:
def send(self,msg_):
"""
Send the alert message
:param str msg_: the message to send
"""
self.msg_ = msg_
ar = alert.Alert()
ar.send_message(msg_)
def monitor(self):
"""
Post to the log file and
send the alert message when
applicable
"""
read = r.SensorReading()
msg_ = read.get_message()
msg_ = read.get_message() # the data
if msg_: # if there is data in general...
x = read.get_failed() # store bad data
msg_ += self.write_avg(read)
msg_ += "==============================================="
self.ctlog.update_templog(msg_) # write general data to log
if x:
self.send(x) # if bad data, send...

This is exactly the kind of case you want to use threading/subprocesses for. Fork off a thread for the email, which times out after a while, and keep your daemon running normally.

Possible approaches that come to mind:
Multiprocessing
Multithreading
Parallel Python
My personal choice would be multiprocessing as you clearly mentioned independent processes; you wouldn't want a crashing thread to interrupt the other function.
You may also refer this before making your design choice: Multiprocessing vs Threading Python

Thanks everyone for the responses. It helped very much. I went with threading, but also updated the code to be sure it handled failing threads. Ran some regressions and found that the subsequent processes were no longer being interrupted by stalled connections and the log was being updated on a consistent schedule . Thanks again!!

Listening for GPIB events

I am controlling a test system using PyVisa/GPIB. The system is comprised of two separate testers (A and B) and a laptop. The the laptop passively listens for a GPIB message from tester A, when received the laptop triggers tester B.
I am using the following code to passively listen for events from tester A:
rm = visa.ResourceManager()
con = "GPIB0::3"
tester_A = rm.get_instrument(con, timeout=5000)
while True:
event = None
try:
event = tester_A.read_raw()
except VisaIOError:
logger.warning("Timeout expired.")
if event != None:
# Do something
Is there a better way to listen and respond to events from tester A? Is there a better way to control this system via GPIB?

The approach you describe will work, but as you are experiencing, is not ideal if you are not quite sure when the instrument is going to respond. The solution lies in using the GPIB's service request (SRQ) functionality.
In brief, the GPIB connection also provides various status registers that allow you to quickly check, for example, whether the instrument is on, whether an error has occurred, etc. (pretty picture). Some of the bits in this register can be set so that they turn on or off after particular events, for example when an operation is complete. This means you tell the instrument to execute a series of commands that you suspect will take a while, and to then flip a bit in the status register to indicate it is done.
From within your software you can do a number of things to make use of this:
Keep looping through a while loop until the status bit indicates that the operation is complete - this is very crude and I wouldn't recommend it.
VISA has a viWaitOnEvent function that allows you to wait until the status bit indicatesthat the operation is complete - a good solution if you need all execution to stop until the instrument has taken a measurement.
VISA also allows you to create an event that occurs when the status bit has flipped - This is a particularly nice solution as it allows you to write an event handler to handle the event.

Interact with long running python process

I have a long running python process running headless on a raspberrypi (controlling a garden) like so:
from time import sleep
def run_garden():
while 1:
/* do work */
sleep(60)
if __name__ == "__main__":
run_garden()
The 60 second sleep period is plenty of time for any changes happening in my garden (humidity, air temp, turn on pump, turn off fan etc), BUT what if i want to manually override these things?
Currently, in my /* do work */ loop, i first call out to another server where I keep config variables, and I can update those config variables via a web console, but it lacks any sort of real time feel, because it relies on the 60 second loop (e.g. you might update the web console, and then wait 45 seconds for the desired effect to take effect)
The raspberryPi running run_garden() is dedicated to the garden and it is basically the only thing taking up resources. So i know i have room to do something, I just dont know what.
Once the loop picks up the fact that a config var has been updated, the loop could then do exponential backoff to keep checking for interaction, rather than wait 60 seconds, but it just doesnt feel like that is a whole lot better.
Is there a better way to basically jump into this long running process?

Listen on a socket in your main loop. Use a timeout (e.g. of 60 seconds, the time until the next garden update should be performed) on your socket read calls so you get back to your normal functionality at least every minute when there are no commands coming in.
If you need garden-tending updates to happen no faster than every minute you need to check the time since the last update, since read calls will complete significantly faster when there are commands coming in.

Python's select module sounds like it might be helpful.
If you've ever used the unix analog (for example in socket programming maybe?), then it'll be familiar.
If not, here is the select section of a C sockets reference I often recommend. And here is what looks like a nice writeup of the module.
Warning: the first reference is specifically about C, not Python, but the concept of the select system call is the same, so the discussion might be helpful.
Basically, it allows you to tell it what events you're interested in (for example, socket data arrival, keyboard event), and it'll block either forever, or until a timeout you specify elapses.
If you're using sockets, then adding the socket and stdin to the list of events you're interested in is easy. If you're just looking for a way to "conditionally sleep" for 60 seconds unless/until a keypress is detected, this would work just as well.
EDIT:
Another way to solve this would be to have your raspberry-pi "register" with the server running the web console. This could involve a little bit extra work, but it would give you the realtime effect you're looking for.
Basically, the raspberry-pi "registers" itself, by alerting the server about itself, and the server stores the address of the device. If using TCP, you could keep a connection open (which might be important if you have firewalls to deal with). If using UDP you could bind the port on the device before registering, allowing the server to respond to the source address of the "announcement".
Once announced, when config. options change on the server, one of two things usually happen:
A) You send a tiny "ping" (in the general sense, not the ICMP host detection protocol) to the device alerting it that config options have changed. At this point the host would immediately request the full config. set, acquiring the update with it.
B) You send the updated config. option (or maybe the entire config. set) back to the device. This decreases the number of messages between the device and server, but would probably take more work as it seems like more a deviation from your current setup.

Why not use an event based loop instead of sleeping for a certain amount of time.
That way your loop will only run when a change is detected, and it will always run when a change is detected (which is the point of your question?).
You can do such a thing by using:
python event objects
Just wait for one or all of your event objects to be triggered and run the loop. You can also wait for X events to be done, etc, depending if you expect one variable to be updated a lot.
Or even a system like:
broadcasting events