Google Drive: Installing the windows client (filesystem plugin)

Google drive can be used without using a browser  via

You have to choose "Download Google Drive":

After Clicking "Download Google Drive" you get:

After these dialogs you got the file googledrivesync.exe (about 700kB). But this is only a installer which downloads the real drive software:

After the installation is done, you have to provide your Credentials for Google Drive:

Then the following two windows are shown:

In your file explorer you can find the following folder after this installation:

Every file or folder inside this Google Drive folder is marked with green checkmark (synced) or two arrows arranged in a circle (synchronizing).

For linux there is (up to now) no drive software available....

Google Drive: first steps and how to upload files...

This week google released google drive. After registering one day later i got my personal cloud space:

After this short intro you are directed to your web user interface:

The menu bar on the left side contains all operations to create or share files:

All administration commands are placed there, but how can i upload files?
Just use this Button (the right one):

and you get:

After that you can edit your files via google docs:

Java 7 g1 garbage collector documentation

A few days ago Oracle announced the schedule for JDK 8. There are many inofficial articles about new features for Java 8 but in my opinion still some documentation for the new features of Java 7 is missing.
I searched for descriptions of the new garbage collector g1 and found only the following two articles:

• http://docs.oracle.com/javase/7/docs/technotes/guides/vm/G1.html
  This article is more a whitepaper:
  

  G1 is the long term replacement of the Concurrent
  Mark-Sweep Collector (CMS). [...] The heap is partitioned into a set of equal-sized heap
  regions, each a contiguous range of virtual memory. G1 compacts as
  it proceeds. It copies objects from one area of the heap to the
  other. Thus, it will not encounter fragmentation issues that CMS
  might encounter.

• http://www.oracle.com/technetwork/java/javase/tech/g1-intro-jsp-135488.html
  This article contains a description and is the only official source to get the command line options to use this garbage collector:
  

  G1 is still considered experimental and can be enabled with the following two parameters:

  
  

  -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC
  To set a GC pause time goal, use the following parameter:
  
  -XX:MaxGCPauseMillis =50 (for a pause time target of 50ms)
  

  
  

But it is amazing, that there is no more documentation, graph, etc available for this important new feature....

Monitoring system calls on your linux: strace

Today i wanted to see the system calls of one of my processes on my laptop. A nice tool for doing this is strace. On a debian system you can this via

apt-get install strace

If you want to see, what your bash is doing just take the PID of your bash and do in another shell:

schroff@hades:$ strace -p 25551
Process 25551 attached - interrupt to quit
read(0,

Doing a ls results in something like this:

Process 25551 attached - interrupt to quit
read(0, "l", 1)                         = 1
rt_sigprocmask(SIG_BLOCK, [INT], [], 8) = 0
write(2, "l", 1)                        = 1
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
read(0, "s", 1)                         = 1
rt_sigprocmask(SIG_BLOCK, [INT], [], 8) = 0
write(2, "s", 1)                        = 1
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
read(0, "\r", 1)                        = 1
write(2, "\n", 1)                       = 1
rt_sigprocmask(SIG_BLOCK, [INT], [], 8) = 0
ioctl(0, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig -icanon -echo ...}) = 0
ioctl(0, SNDCTL_TMR_STOP or TCSETSW, {B38400 opost isig icanon echo ...}) = 0
ioctl(0, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigaction(SIGINT, {0x809c7c0, [], 0}, {0x80e2d40, [], 0}, 8) = 0
rt_sigaction(SIGTERM, {SIG_IGN, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGQUIT, {SIG_IGN, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGALRM, {0x809c500, [HUP INT ILL TRAP ABRT BUS FPE USR1 SEGV USR2 PIPE ALRM TERM XCPU XFSZ VTALRM SYS], 0}, {0x80e2d40, [], 0}, 8) = 0
rt_sigaction(SIGTSTP, {SIG_IGN, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGTTOU, {SIG_IGN, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGTTIN, {SIG_IGN, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGWINCH, {0x809c310, [], 0}, {0x80e2c20, [], SA_RESTART}, 8) = 0
rt_sigaction(SIGINT, {0x809c7c0, [], 0}, {0x809c7c0, [], 0}, 8) = 0
time(NULL)                              = 1333218356
rt_sigprocmask(SIG_BLOCK, [INT CHLD], [], 8) = 0
pipe([3, 4])                            = 0
clone(child_stack=0, flags=CLONE_CHILD_CLEARTID|CLONE_CHILD_SETTID|SIGCHLD, child_tidptr=0xb766f728) = 27965
setpgid(27965, 27965)                   = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
close(3)                                = 0
close(4)                                = 0
ioctl(255, TIOCGPGRP, [25551])          = 0
rt_sigprocmask(SIG_BLOCK, [CHLD TSTP TTIN TTOU], [CHLD], 8) = 0
ioctl(255, TIOCSPGRP, [27965])          = 0
rt_sigprocmask(SIG_SETMASK, [CHLD], NULL, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [CHLD], [], 8) = 0
waitpid(-1, [{WIFEXITED(s) && WEXITSTATUS(s) == 0}], WSTOPPED|WCONTINUED) = 27965
rt_sigprocmask(SIG_BLOCK, [CHLD TSTP TTIN TTOU], [CHLD], 8) = 0
ioctl(255, TIOCSPGRP, [25551])          = 0
rt_sigprocmask(SIG_SETMASK, [CHLD], NULL, 8) = 0
ioctl(255, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(255, TIOCGWINSZ, {ws_row=24, ws_col=80, ws_xpixel=499, ws_ypixel=316}) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
--- SIGCHLD (Child exited) @ 0 (0) ---
waitpid(-1, 0xbfc693fc, WNOHANG|WSTOPPED|WCONTINUED) = -1 ECHILD (No child processes)
sigreturn()                             = ? (mask now [])
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
rt_sigaction(SIGINT, {0x809c7c0, [], 0}, {0x809c7c0, [], 0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
write(1, "\33]0;schroff@hades: /tmp\7", 24) = 24
stat64("/home/schroff/.bash_history", {st_mode=S_IFREG|0644, st_size=316074, ...}) = 0
open("/home/schroff/.bash_history", O_WRONLY|O_APPEND|O_LARGEFILE) = 3
write(3, "ls\n", 3)                     = 3
close(3)                                = 0
time(NULL)                              = 1333218356
time(NULL)                              = 1333218356
rt_sigprocmask(SIG_BLOCK, [CHLD TSTP TTIN TTOU], [], 8) = 0
ioctl(255, TIOCSPGRP, [25551])          = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigaction(SIGINT, {0x809c7c0, [], 0}, {0x809c7c0, [], 0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, [INT], [], 8) = 0
ioctl(0, TIOCGWINSZ, {ws_row=24, ws_col=80, ws_xpixel=499, ws_ypixel=316}) = 0
ioctl(0, TIOCSWINSZ, {ws_row=24, ws_col=80, ws_xpixel=499, ws_ypixel=316}) = 0
ioctl(0, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(0, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig icanon echo ...}) = 0
ioctl(0, SNDCTL_TMR_STOP or TCSETSW, {B38400 opost isig -icanon -echo ...}) = 0
ioctl(0, SNDCTL_TMR_TIMEBASE or TCGETS, {B38400 opost isig -icanon -echo ...}) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, [INT QUIT ALRM TERM TSTP TTIN TTOU], [], 8) = 0
rt_sigaction(SIGINT, {0x80e2d40, [], 0}, {0x809c7c0, [], 0}, 8) = 0
rt_sigaction(SIGTERM, {0x80e2d40, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGTERM, {SIG_IGN, [], 0}, {0x80e2d40, [], 0}, 8) = 0
rt_sigaction(SIGQUIT, {0x80e2d40, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGQUIT, {SIG_IGN, [], 0}, {0x80e2d40, [], 0}, 8) = 0
rt_sigaction(SIGALRM, {0x80e2d40, [], 0}, {0x809c500, [HUP INT ILL TRAP ABRT BUS FPE USR1 SEGV USR2 PIPE ALRM TERM XCPU XFSZ VTALRM SYS], 0}, 8) = 0
rt_sigaction(SIGTSTP, {0x80e2d40, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGTSTP, {SIG_IGN, [], 0}, {0x80e2d40, [], 0}, 8) = 0
rt_sigaction(SIGTTOU, {0x80e2d40, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGTTOU, {SIG_IGN, [], 0}, {0x80e2d40, [], 0}, 8) = 0
rt_sigaction(SIGTTIN, {0x80e2d40, [], 0}, {SIG_IGN, [], 0}, 8) = 0
rt_sigaction(SIGTTIN, {SIG_IGN, [], 0}, {0x80e2d40, [], 0}, 8) = 0
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigaction(SIGWINCH, {0x80e2c20, [], SA_RESTART}, {0x809c310, [], 0}, 8) = 0
rt_sigprocmask(SIG_BLOCK, [INT], [], 8) = 0
write(2, "schroff@hades:$ ", 16)        = 16
rt_sigprocmask(SIG_SETMASK, [], NULL, 8) = 0
rt_sigprocmask(SIG_BLOCK, NULL, [], 8)  = 0
read(0, ^[[B

Ok - a lot of output and not really readable. But with -o you can pipe the output into a file and this you can use for statistics:

schroff@hades:$ cat /tmp/test |awk -F \( '{print $1}'|sort|uniq -c|sort -n
      1 clone
      1 open
      1 pipe
      1 setpgid
      1 --- SIGCHLD
      1 sigreturn
      1 stat64
      2 waitpid
      3 close
      3 time
      4 read
      6 write
     15 ioctl
     24 rt_sigaction
     29 rt_sigprocmask

Ok, it is not clear if this is more helpful, but you can at least see what files are opened by your program very easily:

 open("/foo/bar", O_RDONLY) = -1 ENOENT (No such file or directory)

Or you can detect all signals sent to this program, like shown here:

--- SIGTERM (Terminated) @ 0 (0) ---
read(0,  <unfinished ...>
+++ killed by SIGKILL +++