12-14-2009
Corona688, thanks for your input. But I think you agree with me that that's not exaclty it. With strace I cannot see how exactly read/write API calls are mapped into block devide requests, next - a very important one - I cannot see how efficiently I utilize FS. For example on some filesystems I have to allocate file in large chunks and then fseek, on others I have to append, so on... - all these choises become obvious once I can see what's going on under the hood...
PS
I think once I found a tool that did exactly what I need by installing a driver under /proc but now I can't find it anymore...
10 More Discussions You Might Find Interesting
1. Programming
I have two net-card. one is 172.16.24.99(ENG) ,another is 172.16.25.99(ENG-B). Both masks is 255.255.255.0.
I will monitor data on the tcp port 8055 in ENG, How do I set option of tcpdump command (2 Replies)
Discussion started by: chenhao_no1
2 Replies
2. UNIX for Dummies Questions & Answers
does anybody know what the -d -dd and -ddd options are used for ?
thanks (2 Replies)
Discussion started by: ant04
2 Replies
3. Cybersecurity
i would like to know about tcpdump
i would like to use tcpdump to get information about these
- Date
- time
- source hostname
- source mac address
- source ip address
- destination ip address
- see outbound only
then i use command like this
tcpdump -i le0 -n -q -tttt -e src net... (0 Replies)
Discussion started by: chamnanpol
0 Replies
4. IP Networking
i would like to know about tcpdump
i would like to use tcpdump to get information about these
- Date
- time
- source hostname
- source mac address
- source ip address
- destination ip address
- see outbound only
then i use command like this
tcpdump -i le0 -n -q -tttt -e src net... (2 Replies)
Discussion started by: chamnanpol
2 Replies
5. AIX
I'm search for a disk exerciser / load tool like iometer, iozone, diskx for IBM AIX 5.2 and 5.3
Because of a very bad disk performance on several AIX systems, I need to have a tool which is able to generate a disk load on my local and SAN disks.
Does somebody knows a kind of tool which is... (5 Replies)
Discussion started by: funsje
5 Replies
6. IP Networking
Hello !
I am using
tcpdump -w /tr.cap -p -n -s 0 "udp"
to trace my network trafic.
(analysing later)
I want to reduce the size of the trace files.
Firtst i can use the great -C option but old files are not deleted...
Second I don't want trace RTP packet but i can't find how to use... (1 Reply)
Discussion started by: Calimero90
1 Replies
7. Solaris
Hi All
Currently i had a server directly connect to the EMC box.
The EMC storage is a FC Direct Attached Storage to the server without going through SAN switches
And i had download the Daily data file in /var/adm/sa/sardd
But i not sure which one in /var/adm/sa/sardd is the correct... (14 Replies)
Discussion started by: SmartAntz
14 Replies
8. Programming
Writing a Tool to simulate non-sequential disk I/O (simulate db file sequential read) in C POSIX
I have over the years come across the same issue a couple of times, and it normally is that the read speed on SAN is absolutely atrocious when doing non-sequential I/O to the disks. Problem being of... (7 Replies)
Discussion started by: vrghost
7 Replies
9. Debian
Hi.
Need Help with TcpDump
Trying to sniff associatio-request with tcpdump but when i run this tcpdump -i eth0 wlan subtype assoc-req i get this error
can anyone help me with this error ? Thanks alot !!:) (1 Reply)
Discussion started by: SoulZB
1 Replies
10. IP Networking
I've recently started learning to use TCPdump, and I find it pretty interesting. There's one thing I don't understand. When I tell it to capture packets on, say, the WiFi interface en1, it often captures packets sent or received by other hosts on the network. How can it do this? My... (3 Replies)
Discussion started by: Ultrix
3 Replies
strace(1M) strace(1M)
NAME
strace - write STREAMS event trace messages to standard output
SYNOPSIS
mod sub pri
DESCRIPTION
gets STREAMS event trace messages from STREAMS drivers and modules via the STREAMS log driver and writes these messages to standard output.
By default, without arguments writes all STREAMS trace messages from all drivers and modules. with command-line arguments limits the trace
messages received.
The arguments, which must be specified in groups of three, are:
mod Specifies the STREAMS module identification number from the streamtab entry.
sub Specifies a subidentification number (often corresponding to a minor device).
pri Specifies a tracing priority level. gets messages of a level equal to or less than the value specified by pri. Only posi-
tive integer values are allowed.
The value can be used for any argument in the command line to indicate that there are no restrictions for that argument.
Multiple sets of the three arguments can be specified to obtain the messages from more than one driver or module.
Only one process can open the STREAMS log driver at a time.
When is invoked, the log driver compares the sets of command line arguments with actual trace messages, returning only messages that sat-
isfy the specified criteria.
STREAMS event trace messages have the following format:
seq time tick pri ind mod sub text
Components are interpreted as follows:
seq Trace event sequence number.
time Time the message was sent expressed in hh:mm:ss.
tick Time the message was sent expressed in machine ticks since the last boot.
pri Tracing priority level as defined by the STREAMS driver or module that originates the messages.
ind Can be any combination of the following three message indicators:
The message has also been saved in the error log.
The message signaled a fatal error.
The message has also been mailed to the system administrator.
mod Module identification number of the trace message source.
sub Subidentification number of the trace message source.
text Trace message text.
runs until terminated by the user.
EXAMPLES
Display all trace messages received from the driver or module identified by mod
Display trace messages of any tracing priority level from the driver or module identified by mod and its minor devices identified by the
sub or
Display the trace messages from the same driver or module and subs but limit the priority levels to 0 for subs 2 and 3; 1 for sub 4, driver
or module
WARNINGS
Running with several sets of arguments can impair STREAMS performance, particularly for those modules and drivers that are sending the mes-
sages.
Also be aware that may not be able to handle a large number of messages. If drivers and modules return messages to too quickly, some may
be lost.
FILES
NLS catalog for
SEE ALSO
strclean(1M), strerr(1M), strlog(7).
strace(1M)