Displaying 20 results from an estimated 600 matches similar to: "IO probes and forcedirectio"
2008 Dec 02
18
How to dig deeper
In order to get more information on IO performance problems I created the script below:
#!/usr/sbin/dtrace -s
#pragma D option flowindent
syscall::*write*:entry
/pid == $1 && guard++ == 0/
{
self -> ts = timestamp;
self->traceme = 1;
printf("fd: %d", arg0);
}
fbt:::
/self->traceme/
{
/* elapsd =timestamp - self -> ts;
printf("
2010 Feb 19
3
samba file locking
Hi samba experts,
We have a strange file locking problem and i hope someone can help. We use
some CentOS 5 servers, which use samba 3.0.33, to share files of a java
application to clients. Clients are mostly CentOS 5 (same version as the
server), but there are a few legacy windows clients (the reason why we use
samba and not nfs). And now the problem. When our developer uploads a new
jar file to
2008 Aug 13
1
tracing blocks behind I/O
Hi,
I know how to trace the number of bytes read/written by a program by summing the argument of that read/write syscall. However, the way the OS services read/write calls is in blocks. I wonder if it''s possible to trace the actual number of blocks read/written caused by the syscalls?
--
This message posted from opensolaris.org
2008 Jun 09
6
Dtrace on OpenSolaris/VirtualBox
I''m running OpenSolaris 2008.05 in VirtualBox on a Windows XP host. Playing around with various probes, I found that trying to load any probe associated with bdev_strategy dumps core.
I can think of one or two likely and reasonable causes for this, but am assuming it''s undesirable behavior.
Anyone know what''s happening here?
--
This message posted from
2005 Sep 16
5
ddi_pathname
Hello,
I can see that there is an implementation/emulation of ddi_pathname in DTrace, but I''m a bit confused about the capabilities and invocation of this function. I would like to diplay the path to the block device from bdev_strategy and other io:genunix::start probes.
If someone is familiar with ddi_pathname, could you please provide an example invocation?
Thanks,
Michael
This
2008 Apr 01
3
Xen without APIC
Hi,
I am trying to boot Xen on top of a simulator. I am having problems with the
APIC module in my simulator, not related to Xen. So, I want to boot Xen
without APIC support. Is there a way to disable APIC support in Xen? I am
fine even Xen is restricted to uni-processor environment.
Thanks,
Bhaskar
_______________________________________________
Xen-users mailing list
2009 Dec 17
3
Looking for help on 2 items...
I am pretty new to Dtrace but use the Dtrace Toolkit when trying to
troubleshoot I/O issues
On Oracle.
I am looking for help on how to do the following:
I am trying to answer whether adding more HBA Cards/ports
would be effective.
To do this, I need to know the i/o''s per second
As well as total bandwidth per second.
Has anyone done this before?
Does anyone have any other ideas on how
2007 Sep 18
3
newbie question about a dbuf-arc eviction race
Hi,
Can a dbuf be in DB_CACHED state, db_holds == 0,
b_efunc != NULL while its db_buf is put on the
eviction list ? From an ASSERT in dbuf_do_evict(),
it appears that it can. If it can, I am wondering what
is preventing the following race
dbuf_hold_impl()
db = dbuf_find(dn, level, blkid);
...
if (db->db_buf && refcount_is_zero(&db->db_holds)) {
2007 May 29
6
NCQ performance
I''ve been looking into the performance impact of NCQ. Here''s what i
found out:
http://blogs.sun.com/erickustarz/entry/ncq_performance_analysis
Curiously, there''s not too much performance data on NCQ available via
a google search ...
enjoy,
eric
2008 Apr 01
2
Xen Log messages
Hi,
I am a newbie to Xen. How can I see the Xen hypervisor boot messages? Is
there any command similar to dmesg to check the boot log of Xen?
Thanks,
Bhaskar
_______________________________________________
Xen-users mailing list
Xen-users@lists.xensource.com
http://lists.xensource.com/xen-users
2017 Jun 26
3
Request for help - adding text files to a data frame
Hello Everyone,
I have a data frame which looks something like this:
V1 <-c(1,2,3)
V2 <-c(5,6,7)
V3 <-c(9,10,11)
df <- data.frame(V1,V2,V3)
I want to add couple of text files at the beginning of df and save
the df as a csv file.
The csv file should look something like this:
"AAAAAAAA"
"BBBBBBBBB"
"CCCCCCCCC"
V1 V2 V3
1 5 9
2
2008 Aug 05
4
Mini-OS and Xen!
Hi I have a doubt regarding Mini-OS and Xen. If it is true that Xen reserves in the virtual address space the top 64MB on 32bit systems and 168MB in PAE systems, doesn''t it exist with a Mini-OS kernel which has only 32MB in size i.e. going by its default config file? Obviously I''m missing something.
Regards,
Bhaskar.
_______________________________________________
Xen-devel
2008 Jan 31
1
simulating directio on zfs?
The big problem that I have with non-directio is that buffering delays program execution. When reading/writing files that are many times larger than RAM without directio, it is very apparent that system response drops through the floor- it can take several minutes for an ssh login to prompt for a password. This is true both for UFS and ZFS.
Repeat the exercise with directio on UFS and there is no
2012 Jun 04
2
Frequently login problem
Hi,
I am using dovecot 2.1.3 on centos 5.7. It was working fine but last few
days I need to restart or reload dovecot service because at that time users
are not able to login.
Each time I am getting information from doveco.log is as :
Jun 04 11:52:54 auth: Error: BUG: Authentication client gave a PID 17564 of
existing connection
Jun 04 11:52:54 auth: Error: BUG: Authentication client gave a PID
2009 Apr 20
6
simulating directio on zfs?
I had to let this go and get on with testing DB2 on Solaris. I had to
abandon zfs on local discs in x64 Solaris 10 5/08.
The situation was that:
* DB2 buffer pools occupied up to 90% of 32GB RAM on each host
* DB2 cached the entire database in its buffer pools
o having the file system repeat this was not helpful
* running high-load DB2 tests for 2 weeks showed 100%
2011 Oct 26
1
Re: ceph on btrfs [was Re: ceph on non-btrfs file systems]
2011/10/26 Sage Weil <sage@newdream.net>:
> On Wed, 26 Oct 2011, Christian Brunner wrote:
>> >> > Christian, have you tweaked those settings in your ceph.conf? It would be
>> >> > something like ''journal dio = false''. If not, can you verify that
>> >> > directio shows true when the journal is initialized from your osd log?
2007 Nov 21
1
OpenSolaris not booting
I finally managed to tar the kernel and install it but it doesn’t boot the system and now I get the following error: -
Failed to get ramdisk from boot
Unexpected trap
Error code, optional 0x0
Code segment 0x28
Flags register 0x10046
Retyrn %rsp 0xc0cfd0
Return %ss 0x8
There is no stack trace and I get a similar error right below the one above when the system tries to backtrace and it says
2007 Nov 21
6
Compiling issue on x86!
Hi thanks for your posts so far. Since what I had assumed was a 32 bit kernel which I compiled didn''t work, I religiously set out on compiling a 64 bit version as my system is currently booted in 64 bit mode.
I installed SUNStudio12 on the system and set the SPRO_VROOT to point towards it and when I do a make all in usr/src directory, I get the following error when make cwds and runs in
2006 Oct 15
3
open(2) O_DIRECT on smbmount gives EINVAL
Does samba 3.0.23c not support the use of O_DIRECT? When I try to open an
smbmount'd file using O_DIRECT, I get EINVAL. I am able to use O_DIRECT with no
problems on a block device and nfs mounts, so I know the kernel supports it.
samba: 3.0.23c
kernel: 2.6.9-42.0.3.EL (32-bit)
I am using the below code for my test. smb fails on open(2).
#include <fcntl.h>
#include
2007 Oct 08
2
safe zfs-level snapshots with a UFS-on-ZVOL filesystem?
I had some trouble installing a zone on ZFS with S10u4
(bug in the postgres packages) that went away when I used a
ZVOL-backed UFS filesystem
for the zonepath.
I thought I''d push on with the experiment (in the hope Live Upgrade
would be able to upgrade such a zone).
It''s a bit unwieldy, but everything worked reasonably well -
performance isn''t much worse than straight