Check out this PrestaShop blog post for interesting tidbits such as:
Increase value for the same price
Believe it or not, consumers prefer to get more for the same price than to get a discount on the product. This is why you often see “33% more” on hygiene and food products. Psychologically, the 33% more for free sounds better than a 33% discount off the products price.
here.
Use iotop (thanks Guillaume Chazarain) to figure out (thanks Paul Wise) where the issue is at.
iotop(1) – Linux man page
Name
iotop – simple top-like I/O monitor
Synopsis
iotop [OPTIONS]
Description
iotop watches I/O usage information output by the Linux kernel (requires 2.6.20 or later) and displays a table of current I/O usage by processes or threads on the system. At least the CONFIG_TASK_DELAY_ACCT and CONFIG_TASK_IO_ACCOUNTING options need to be enabled in your Linux kernel build configuration, these options depend on CONFIG_TASKSTATS.
iotop displays columns for the I/O bandwidth read and written by each process/thread during the sampling period. It also displays the percentage of time the thread/process spent while swapping in and while waiting on I/O. For each process, its I/O priority (class/level) is shown. In addition, the total I/O bandwidth read and written during the sampling period is displayed at the top of the interface.
Use the left and right arrows to change the sorting, r to reverse the sorting order, o to toggle the –only option, p to toggle the –processes option, a to toggle the –accumulated option, q to quit or i to change the priority of a thread or a process’ thread(s). Any other key will force a refresh.
Options
–version
- Show the version number and exit
- -h, –help
- Show usage information and exit
- -o, –only
- Only show processes or threads actually doing I/O, instead of showing all processes or threads. This can be dynamically toggled by pressing o.
- -b, –batch
- Turn on non-interactive mode. Useful for logging I/O usage over time.
- -n NUM, –iter=NUM
- Set the number of iterations before quitting (never quit by default). This is most useful in non-interactive mode.
- -d SEC, –delay=SEC
- Set the delay between iterations in seconds (1 second by default). Accepts non-integer values such as 1.1 seconds.
- -p PID, –pid=PID
- A list of processes/threads to monitor (all by default).
- -u USER, –user=USER
- A list of users to monitor (all by default)
- -P, –processes
- Only show processes. Normally iotop shows all threads.
- -a, –accumulated
- Show accumulated I/O instead of bandwidth. In this mode, iotop shows the amount of I/O processes have done since iotop started.
- -k, –kilobytes
- Use kilobytes instead of a human friendly unit. This mode is useful when scripting the batch mode of iotop. Instead of choosing the most appropriate unit iotop will display all sizes in kilobytes.
- -t, –time
- Add a timestamp on each line (implies –batch). Each line will be prefixed by the current time.
- -q, –quiet
- suppress some lines of header (implies –batch). This option can be specified up to three times to remove header lines.
- -qcolumn names are only printed on the first iteration,
column names are never printed,
-qqq
the I/O summary is never printed.
See Also
Author
iotop was written by Guillaume Chazarain.
This manual page was started by Paul Wise for the Debian project and is placed in the public domain.
Daniel Stenberg says, “Don’t email me.”
Yes, I get it. If you are perceived as an expert the emails don’t let up. And I totally agree with the annoyance of being made to look like a jerk for not responding when you are dealing with pressing stuff like a client deadline or a family illness that is demanding massive amounts of your time. The point about using public resources is very true as well. Someone else has had and will have your same question, or something pretty darn close. Post your inquiry in public and multiple people will benefit from your frustration. And indeed yes, there are randoms who think that open source should come with technical support free from financial cost or continued learning on their parts. Finally, it is annoying when people want to be spoon fed after you have laid out a buffet of resources on your website. I get it.
Still, a stock email, written once, with an apology for the impersonal response and a whole list of links usually does the trick.
Gmane is a mailing list archive. Any public mailing list can be carried by Gmane, but the vast majority of the lists here deal with free software. Go check it out: here.
