Thanks for the info. While I was running the sample-bt-off-cpu after installing the systemtap 2.4 and pulled the
nginx-systemtap-toolkit
library, I was getting the following error.
Any insight into the root cause is appreciated. As I mentioned I'm running this in a EC2 with amazon linux.
./sample-bt-off-cpu -p 11333 -t 5
semantic error: while resolving probe point: identifier 'scheduler' at <input>:28:7
source: probe scheduler.cpu_on {
^
semantic error: no match
Pass 2: analysis failed. [man error::pass2]
When I run the stap -V, below is the info I get
stap -V
Systemtap translator/driver (version 2.4/0.158, non-git sources)
Copyright (C) 2005-2013 Red Hat, Inc. and others
This is free software; see the source for copying conditions.
enabled features: TR1_UNORDERED_MAP NLS
I can see the difference in the enabled features. Is that the issue? Any insight into this is highly appreciated.
Thanks
Santi
On Wednesday, 5 March 2014 04:01:56 UTC+5:30, agentzh wrote:
Hello!
On Mon, Mar 3, 2014 at 9:47 PM, santi kumar wrote:
> As suggested we increased chunk size to 32K and the upload times are faster
> relatively. But the slow connections remains slow by the worker processes
> and the process still accepts more connections.
Ensure it is not caused by the slowness in the network between you and
your clients. Tuning NGINX will never help your client's slow wifi
network, for example.
> From 'lsof -P -n -p <PID> I
> can see that it's accepting data from network and writing into the file
> system.
>
This is not really helpful. Because we all know that it should be
doing network and file writes.
> Is there a way to configure nginx to not accept any connection on the
> existing worker process?
>
Are you sure you want to do this? This will simply make your clients
timed out on connecting.
> Definitely this is a candidate for off-cpu analysis. The current setup is
> in Amazon ec2 with Amazon linux. It has systemtap 1.4, but the tool you
> pointed require higher version. Can you point to any documentation for
> installing these tool in AWS EC2.
>
See http://openresty.org/#BuildSystemtap
It's worth mentioning that in one of my EC2 instances running Amazon
Linux AMI, the systemtap in the default repos is 1.8:
$ yum info systemtap
Loaded plugins: auto-update-debuginfo, fastestmirror, priorities,
update-motd, upgrade-helper
Determining fastest mirrors
* amzn-main: packages.us-west-1.amazonaws.com
* amzn-main-debuginfo: packages.us-west-1.amazonaws.com
* amzn-updates: packages.us-west-1.amazonaws.com
* amzn-updates-debuginfo: packages.us-west-1.amazonaws.com
amzn-main/latest/primary_db
| 2.5 MB 00:00
amzn-main-debuginfo/latest/primary_db
| 237 kB 00:00
Available Packages
Name : systemtap
Arch : x86_64
Version : 1.8
Release : 7.15.amzn1
Size : 29 k
Repo : amzn-main/latest
Summary : Programmable system-wide instrumentation system
URL : http://sourceware.org/systemtap/
License : GPLv2+
Description : SystemTap is an instrumentation system for systems
running Linux.
: Developers can write instrumentation scripts to collect data on
: the operation of the system. The base systemtap
package contains/requires
: the components needed to locally develop and execute
systemtap scripts.
Regards,
-agentzh
