[lttng-dev] 回复:Re: 回复:Re: 回复:Re: Pros and Cons of LTTng

Tue Aug 20 12:02:20 EDT 2019

Hi Hai,

Sorry for the delay.

The main obstruction to kernel tracing support for RHEL6 is indeed the kernel.

Note that we dropped the patches in the master branch:

  commit ca2fca6b64297227b2565773a495803aa90c148e
  Author: Michael Jeanson <mjeanson at efficios.com>
  Date:   Thu Nov 8 15:24:01 2018 -0500

      Drop compat patches for kernels < 2.6.36

      Signed-off-by: Michael Jeanson <mjeanson at efficios.com>
      Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>

Still, the stable 2.10 branch still carries the patches that you would need [1].
As previously mentioned, those patches might not apply cleanly since it has
been a while any effort was put in testing against RHEL6.

[1] https://github.com/lttng/lttng-modules/tree/stable-2.10/linux-patches

Cheers

On Fri, Aug 09, 2019 at 07:44:57AM +0800, 杨海 wrote:
> Hi Mathieu,
> 
> We aim to trace SYSCALL in kernel space. In general, what would be the obstacles to support RHEL6? Or what are key kernel patches to be necessary? 
> 
> 
> Regards
> Hai 
> 
> 
> 
> 
> 
> 
> 
> --------------原始邮件--------------
> 发件人："Mathieu Desnoyers "<mathieu.desnoyers at efficios.com>;
> 发送时间：2019年7月30日(星期二) 晚上10:04
> 收件人："杨海" <hai.yang at magic-shield.com>;
> 抄送："Jonathan Rajotte "<jonathan.rajotte-julien at efficios.com>;"lttng-dev "<lttng-dev at lists.lttng.org>;
> 主题：Re: [lttng-dev] 回复:Re:  回复:Re:  Pros and Cons of LTTng
> -----------------------------------
> 
>  Hi,
> 
> 
> 
> The current LTTng kernel tracer (lttng-modules) supports Linux 3.0+ only.
> 
> 
> 
> If you only need to trace user-space, you might be able to use lttng-tools and lttng-ust
> 
> on an older kernel. Please refer to the README.md files of each project for information
> 
> about their environment prerequisites.
> 
> 
> 
> The RHEL6 kernel variant based on 2.6.32-2.6.35 Linux kernels has never been supported by
> 
> the LTTng 2.x kernel tracers without kernel patching.
> 
> 
> 
> Thanks,
> 
> 
> 
> Mathieu
> 
> 
> 
> ----- On Jul 29, 2019, at 8:34 PM, 杨海 <hai.yang at magic-shield.com> wrote:
> 
> Hi Mathieu,
> Thanks. I am looking for packages for older distributions like CentOS 6 (with kernel 2.6) but could not find it. And which kernel version is minimum requirement for LTTng?
> 
> Regards
> Hai
> 
> 
> 
> 
> 
> ------------------ Original ------------------
> From:  "Mathieu Desnoyers"<mathieu.desnoyers at efficios.com>;
> Date:  Thu, Jul 25, 2019 11:48 PM
> To:  "杨海"<hai.yang at magic-shield.com>; 
> Cc:  "Jonathan Rajotte"<jonathan.rajotte-julien at efficios.com>; "lttng-dev"<lttng-dev at lists.lttng.org>; 
> Subject:  Re: [lttng-dev] 回复:Re:  回复:Re:  Pros and Cons of LTTng
> 
>  
> ----- On Jul 25, 2019, at 4:21 PM, 杨海 <hai.yang at magic-shield.com> wrote:
> 
> Hi
> 
> Thanks for quick response. 
> LTTng is really impressive on performance，especially under heavy workload. When using it on critical machines，stability is also essential. 
> I wonder how LTTng is commercialized and any products or OS distributions already enabled it. 
> I took a look at lttng-modules bug list，there are a few kernel oops years ago and got resolved. May I say it is very stable or it has not been fully tested? 
> 
> Hi,
> 
> 
> EfficiOS has had commercial customers using LTTng in production for many years now.
> LTTng per-se is distributed as packages in all major Linux distributions. EfficiOS also provides
> 
> more up-to-date packages for some distributions through http://packages.efficios.com/
> 
> 
> The way we commercialize LTTng is through funding for design and implementation of
> customer's feature requests. We also provide commercial support tailored to specific
> customer's environments, which includes SLA and continuous integration testing of specific
> environments.
> 
> 
> If those are services you are interested in, please feel free to contact us in private so we
> can further discuss your needs.
> 
> 
> Best regards,
> 
> 
> Mathieu
> 
> 
> regards
> Hai
> 
> 
> 
> 
> 
> 
> --------------原始邮件--------------
> 发件人："Jonathan Rajotte-Julien "<jonathan.rajotte-julien at efficios.com>;
> 发送时间：2019年7月23日(星期二) 上午6:20
> 收件人："杨海" <hai.yang at magic-shield.com>;
> 抄送："lttng-dev "<lttng-dev at lists.lttng.org>;
> 主题：Re:  回复:Re: [lttng-dev] Pros and Cons of LTTng
> -----------------------------------
> 
>  Hi,
> 
> > As to LD_PRELOAD, it is also used for privilege escalation. Will it be regarded as vulnerability and forbidden on some Linux systems?
> 
> It could yes.
> In that case you will be limited to the syscalls interface for the libc
> observability unless you instrument it and distribute it.
> 
> Cheers.
> 
> 
> 
> _______________________________________________
> lttng-dev mailing list
> lttng-dev at lists.lttng.org
> https://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev
> 
> 
> -- 
> 
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com
> 
>  
> 
> 
> 
> 
> 
> 
> -- 
> 
> Mathieu Desnoyers
> EfficiOS Inc.
> http://www.efficios.com

-- 
Jonathan Rajotte-Julien
EfficiOS