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vsftpd ftp

 ftp

1> yum install vsftpd

2>

sh-4.2# systemctl enable vsftpd      

Created symlink from /etc/systemd/system/multi-user.target.wants/vsftpd.service to /usr/lib/systemd/system/vsftpd.service.

sh-4.2# systemctl start vsftpd

sh-4.2#

3> 

sh-4.2# systemctl status vsftpd

* vsftpd.service - Vsftpd ftp daemon

   Loaded: loaded (/usr/lib/systemd/system/vsftpd.service; enabled; vendor preset: disabled)

   Active: active (running) since Mon 2021-05-17 00:25:50 PDT; 16s ago

  Process: 5701 ExecStart=/usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf (code=exited, status=0/SUCCESS)

 Main PID: 5702 (vsftpd)

   CGroup: /system.slice/vsftpd.service

           `-5702 /usr/sbin/vsftpd /etc/vsftpd/vsftpd.conf

May 17 00:25:50 den03ceh systemd[1]: Starting Vsftpd ftp daemon...

May 17 00:25:50 den03ceh systemd[1]: Started Vsftpd ftp daemon.

sh-4.2#

4>

Bugs to Code Ratio

Bugs to Code Ratio

 

Nice insight.

https://www.mayerdan.com/ruby/2012/11/11/bugs-per-line-of-code-ratio

 

(a) Industry Average: "about 15 - 50 errors per 1000 lines of delivered
code." He further says this is usually representative of code that has some
level of structured programming behind it, but probably includes a mix of
coding techniques.

(b) Microsoft Applications: "about 10 - 20 defects per 1000 lines of code
during in-house testing, and 0.5 defect per KLOC (KLOC IS CALLED AS 1000 lines of code) in released
product (Moore 1992)." He attributes this to a combination of code-reading
techniques and independent testing (discussed further in another chapter of
his book).

(c) "Harlan Mills pioneered 'cleanroom development', a technique that has
been able to achieve rates as low as 3 defects per 1000 lines of code during
in-house testing and 0.1 defect per 1000 lines of code in released product
(Cobb and Mills 1990). A few projects - for example, the space-shuttle
software - have achieved a level of 0 defects in 500,000 lines of code using
a system of format development methods, peer reviews, and statistical
testing."

Performance Problem - compilation of file

 

Performance Problem - compilation of file

 

Figure out the time taken for compilation using

$ /usr/bin/time -p gmake abc.o

...

real 18.02
user 9.88
sys 3.16
$

Check where most of the time is spent

Is that on read, write?

$ strace -c -f -o /tmp/strace_cumm.log gmake file.o

% time     seconds  usecs/call     calls    errors syscall
------ ----------- ----------- --------- --------- ----------------
 92.47   17.289082      508502        34         7 wait4
  2.05    0.382373           2    196871           read
  1.94    0.363374           2    166274           write
  1.52    0.284355          12     24364     19274 open
  0.64    0.120390           3     35024     18381 stat
  0.48    0.089184       89184         1           rename
  0.45    0.083519          16      5189         2 close

...

$

Check if is struck somewhere

strace -T -f -o /tmp/strace.log gmake file.o

In parallel, tail -f /tmp/strace.log

 

Check the speed of access  from NFS

$ dd if=file.c of=/dev/null
1946+1 records in
1946+1 records out
996481 bytes (996 kB) copied, 0.0030956 s, 322 MB/s
$
 

Check NFS IO Stats for the filer

$ nfsiostat <mounted_dir>

<NFS-Server:Export directory> mounted on <mounted_directory>:

   op/s         rpc bklog
 298.56    0.00
read:            ops/s             kB/s           kB/op         retrans         avg RTT (ms)    avg exe (ms)
                  0.828  20.987  25.350       0 (0.0%)   33.982  34.012
write:           ops/s             kB/s           kB/op         retrans         avg RTT (ms)    avg exe (ms)
                  0.000   0.000   0.000       0 (0.0%)    0.000   0.000
$ 

Check pstack of compiler backend

Is that struck somewhere?

Enjoy Experience of Stay at Deoli, Bundi, Kota, Jaipur

Different experience

Life is easy and difficult depending on how we look at it.

It is good to experience life in multiple places. 

The life in Bengaluru is very different. The circle of friends and neighbors is mostly IT folks.

Most of the discussions in Bengaluru revolve around software companies, stock market and sometime on spirituality.

My stay in Jaipur, native Village, Deoli, Bundi and Kota has been always very different.

I have learned to enjoy the experience and journey of life.

Take the things as they come.

The temptation for stock market has been reasonably controlled.

The temptation for real estate in Rajasthan will naturally end once I have found answer to some more questions.

life : yoga and meditation

Life is beautiful. 

Healthy body is the best gift to self.

Spend 1hr on yoga (physical exercise), meditation (mental peace).

number of thoughts

Focus on present to reduce the number of past and futuristic thoughts.