OS Block Size finding command

Hi,
can anybody tell me the command to find the OS block size?
(DB block size should be multiple of OS block size).
PS: i use Red Hat Linux OS. (would be fantastic if you give Sun OS command too)
Regards
Suresh

df -g or fstyp -v
Nicolas.

Similar Messages

How to find block size of my OS

Hi I am using redhat 9, I would like to know how to find out my OS block size as I need to give the database block size accordingly...

I would rather adjust the OS block size to required database block size, not vice versa if possible.
You can check the FILESYSTEM block size using dumpe2fs command (replace /dev/sda5 with your filesystem blocks device):
[root@localhost ~]# dumpe2fs /dev/sda5 | grep "Block size"
dumpe2fs 1.39 (29-May-2006)
Block size: 4096
If you want to know what's the minimum OS block device IO block size (which is not the same thing as filesystem block size), you can do it easily using an Oracle command (if your db is in archivelog mode):
select block_size from v$archived_log where rownum = 1;
Tanel.
http://blog.tanelpoder.com

Finding appropriate block size?

Hi All,
I believe this might be basic question, How to find appropriate block size for building an database to an specific application?
I had seen always default 8K block size is used every where(Around 300-350 databases i have seen till now)....but why and how do they estimate this block size blindly before creating production database.
Also in the same way how memory settings are finalized before creating database?
-Yasser

Yasser,
I have been very fortunate to buy and read several very high quality Oracle books which not only correctly state the way something works, but also manage to provide a logical, reasoned explanation for why things happen as they do, when it is appropriate, and when it is not. While not the first book I read on the topic of Oracle, the book “Oracle Performance Tuning 101” by Gaja Vaidyanatha marked the start of logical reasoning in performance tuning exercises for me. A couple years later I learned that Gaja was a member of the Oaktable Network. I read the book “Expert Oracle One on One” by Tom Kyte and was impressed with the test cases presented in the book which help readers understand the logic of why Oracle behaves as it does, and I also enjoyed the performance tuning stories in the book. A couple years later I found Tom Kyte’s “Expert Oracle Database Architecture” book at a book store and bought it without a second thought; some repetition from his previous book, fewer performance tuning storing, but a lot of great, logically reasoned information. A couple years later I learned that Tom was a member of the Oaktable Network. I read the book “Optimizing Oracle Performance” by Cary Millsap, a book that once again marked a distinct turning point in the method I used for performance tuning – the logic made all of the book easy to understand. A couple years later I learned that Cary was a member of the Oaktable Network. I read the book “Cost-Based Oracle Fundamentals” by Jonathan Lewis, a book by its title seemed to be too much of a beginner’s book until I read the review by Tom Kyte. Needless to say, the book also marked a turning point in the way I approach problem solving through logical reasoning, asking and answering the question – “What is Oracle thinking”. Jonathan is a member of the Oaktable Network, a pattern is starting to develop here. At this point I started looking for anything written in book or blog form by members of the Oaktable Network. I found Richard Foote’s blog, which some how managed to make Oracle indexes interesting for me - probably through the use of logic and test cases which allowed me to reproduce what I reading about. I found Jonathan Lewis’ blog, which covers so many interesting topics about Oracle, all of which leverage logical approaches to help understanding. I also found the blogs of Kevin Closson, Greg Rahn, Tanel Poder, and a number of other members of the Oaktable Network. The draw to the performance tuning side of Oracle administration was primarily for a search for the elusive condition known as Compulsive Tuning Disorder, which was coined in the book written by Gaja. There were, of course, many other books which contributed to my knowledge – I reviewed at least 8 of the Oracle related books on the amazon.com website.
Motivation… it is interesting to read what people write about Oracle. Sometimes what is written directly contradicts what one knows about Oracle. In such cases, it may be a fun exercise to determine if what was written is correct (and why it is logically correct), or why it is wrong (and why it is logically incorrect). Take, for example, the “Top 5 Timed Events” seen in this book (no, I have not read this book, I bumped into it a couple times when performing Google searches):
http://books.google.com/books?id=bxHDtttb0ZAC&pg=PA17#v=onepage&q=&f=false
The text of the book states that the “Top 5 Timed Events” shown indicates a CPU Constrained Database (side note: if a database is a series of files stored physically on a disk, can it ever be CPU constrained?). From the “Top 5 Timed Events”, we see that there were 4,851 waits on the CPU for a total time of 4,042 seconds, and this represented 55.76% of the wait time. Someone reading the book might be left thinking one of:
* “That obviously means that the CPU is overwhelmed!”
* “Wow 4,851 wait events on the CPU, that sure is a lot!”
* “Wow wait events on the CPU, I didn’t know that was possible?”
* “Hey, something is wrong with this ‘Top 5 Timed Events’ output as Oracle never reports the number of waits on CPU.”
* “Something is really wrong with this ‘Top 5 Timed Events’ output as we do not know the number of CPUs in the server (what if there are 32 CPUs), the time range of the statics, and why the average time for a single block read is more than a second!”
A Google search then might take place to determine if anyone else reports the number of waits for the CPU in an Oracle instance:
http://www.google.com/search?num=100&q=Event+Waits+Time+CPU+time+4%2C851+4%2C042
So, it must be correct… or is it? What does the documentation show?
Another page from the same book:
http://books.google.com/books?id=bxHDtttb0ZAC&pg=PA28#v=onepage&q=&f=false
Shows the command:
alter system set optimizer_index_cost_adj=20 scope = pfile;Someone reading the book might be left thinking one of:
* That looks like an easy to implement solution.
* I thought that it was only possible to alter parameters in the spfile with an ALTER SYSTEM command, neat.
* That command will never execute, and should return an “ORA-00922: missing or invalid option” error.
* Why would the author suggest a value of 20 for OPTIMIZER_INDEX_COST_ADJ and not 1, 5, 10, 12, 50, or 100? Are there any side effects? Why isn’t the author recommending the use of system (CPU) statistics to correct the cost of full table scans?
A Google search finds this book (I have not read this book either, just bumped into it during a search) by a different author which also shows that it is possible to alter the pfile through an ALTER SYSTEM command:
http://books.google.com/books?id=ufz5-hXw2_UC&pg=PA158#v=onepage&q=&f=false
So, it must be correct… or is it? What does the documentation show?
Regarding the question of updating my knowledge, I read a lot of books on a wide range of subjects including Oracle, programming, Windows and Linux administration, ERP systems, Microsoft Exchange, telephone systems, etc. I also try to follow Oracle blogs and answer questions in this and other forums (there are a lot of very smart people out there contributing to forums, and I feel fortunate to learn from those people). As long as the book or blog offers logical reasoning, it is fairly easy to tie new material into one’s pre-existing knowledge.
Charles Hooper
IT Manager/Oracle DBA
K&M Machine-Fabricating, Inc.

How to find block size in OS

I know db_block_size and db_file_multiblock_read_count of Oracle should be multiple of OS(operationg System).
Can anybody suggest me , how can i find out block size in window or Linux.
Thanks in advance
Tinku

$show parameter db_block_size this is the setting from your init.ora file.
This parameter is set at the database creation time and cannot be altered.
In linux system use
dumpe2fs -fh /dev/hdb
to get information about your block size.
In my case it was 4k so my db_block_size will be multiples of 4k.
http://www.dizwell.com/html/db_block_size.html
Thanks
Gopal
visit
http://dba.shilpatech.com/

Find command with file size

Hello again,
With my find command I'm trying to get my output to include the file size as it would show in Finder. I believe it's called the "physical" size. Am I going in the right direction with this code or is there a better way?
find /Users/username/Library -name "foo" -prune -maxdepth 3 -exec du -hs {} ;
Thanks again for your input,
Rick

If going down the awk route, might try a slightly different approach
find /Users/username/Library
-name "foo"
-prune
-maxdepth 3
-ls | awk '{print $2 "
" $NF;}'
The -ls avoids invoking a subprocess for every file just so the du command can be called.
The down side is that you do not get benefit of the *du -h* option to humanize the values.
Another approach that would invoke du fewer times would be to put xargs in the pipeline
find /Users/username/Library
-name "foo"
-prune
-maxdepth 3
-print0 | xargs -0 du -hs | awk '{print $1 "
" $2;}'
xargs will bundle up a group of files for each du command to process in one invocation.
The -print0 and -0 will make sure that spaces in file paths do not cause problems for the du command.
Oh yea, if you are going to also be performing a bunch of find commands together, you could do all of those commands in a single pipeline
( find /path1 -name ... -print0;
find /path2 -name ... -print0;
find /path3 -name ... -print0
) | xargs -0 du -hs | awk '{print $1 "
" $2;}'
Message was edited by: BobHarris

How should be set Index block size in Warehouse databases?

Hi,
We have Warehouse database.
I cannot find out index block size.
1. Where can I get know our index block sizes?
2. How can I enlarge index block sizes? Is it related with tablespace?
After your suggestion do I need increase or set buffer cache keep pool according to block sizes? 2K, 4K, 8K, 16K and 32K can be specified?
could you help me please?
thanks and regards,

See the BLOCK_SIZE column in DBA_TABLESPACES.
You can't "increase" the block size. You'd have
a) to allocate DB_xK_cache_size for the new "x"K block size
b) create a new tablespace explicitly specifying the block size in the CREATE TABLESPACE command
c) rebuild your indexes into the new tablespace.
Indexes created in a tablespace with a larger block size have more entries in each block.
You may get better performance.
You may get worse performance.
You may see no difference in performance.
You may encounter bugs.
"increasing block size" is an option to be evaluated and tested thoroughly. It is not, per se, a solution.
Hemant K Chitale
http://hemantoracledba.blogspot.com

Zfs boot block size and ufs boot block size

Hi,
In Solaris UFS file system , boot block resides in 1 to 15 sectors, and each sector is 512 bytes total makes 7680 bytes
bash-3.2# pwd
/usr/platform/SUNW,SPARC-Enterprise-T5220/lib/fs/ufs
bash-3.2# ls -ltr
total 16
-r--r--r-- 1 root sys 7680 Sep 21 2008 bootblk
for zfs file system the boot block size is
bash-3.2# pwd
/usr/platform/SUNW,SPARC-Enterprise-T5220/lib/fs/zfs
bash-3.2# ls -ltr
total 32
-r--r--r-- 1 root sys 15872 Jan 11 2013 bootblk
when we install zfs bootblk on disk using the install boot command ,how many sectors it will use to write the bootblk?
Thanks,
SriKanth Muvva

Thanks for your reply.
my query is when zfs boot block size is 16K, and on disk 1 to 15 sectors(here boot block going to be installed) make around 8K,
it mean in the 16K,it writes only 8K on the disk
if you don't mid will you please explain me in depth
I m referring the doc for UFS, page no 108 ,kernel bootstrap and initialization (its old and its for Solaris 8)
http://books.google.co.in/books?id=r_cecYD4AKkC&printsec=frontcover&source=gbs_ge_summary_r&cad=0#v=onepage&q&f=false
please help me to find a doc for kernel bootstrap and initialization for Solaris 10 with zfs and boot archive
Thanks in advance .
Srikanth

Selection screen - Block Size

hi all
1.how to set a Block size inside the selection screen .
2.how to set a short cut key for a push button.
3.how to set a icon for a push button.
Kindly clarify.
with kind regards
vel

Hello,
Try this
TYPE-POOLS:
icon.    " For Icon
1)
Example.
SELECTION-SCREEN : BEGIN OF BLOCK b3 WITH FRAME TITLE text-t03.
PARAMETERS: y_p_cd RADIOBUTTON GROUP rg1.
SELECTION-SCREEN : END OF BLOCK b4.
2)
SELECTION-SCREEN PUSHBUTTON /1(83) push1
              USER-COMMAND next VISIBLE LENGTH 40.
Create Expand or Collapse Icon For Currency Selection Field
CALL FUNCTION 'ICON_CREATE'
    EXPORTING
      name                  = icon_expand
      text                  = text-x22
    IMPORTING
      RESULT                = push1
    EXCEPTIONS
      icon_not_found        = 1
      outputfield_too_short = 2
      OTHERS                = 3.
IF sy-subrc <> 0.
    MESSAGE ID sy-msgid TYPE y_k_s NUMBER sy-msgno
            WITH sy-msgv1 sy-msgv2 sy-msgv3 sy-msgv4.
ENDIF.
Click on the ICON so that you will find the name of the ICONS.

ORA-00349: failure obtaining block size for '+Z' in Oracle XE

Hello,
I am attempting to move the online redo log files to a new flash recovery area location created on network drive "Z" ( Oracle Database 10g Express Edition Release 10.2.0.1.0).
When I run @?/sqlplus/admin/movelogs; in SQL*Plus as a local sysdba, I get the following errors:
ERROR at line 1:
ORA-00349: failure obtaining block size for '+Z'
ORA-06512: at line 14
Please let me know how to go about resolving this issue.
Thank you.
See below for detail:
Connected.
SQL> @?/sqlplus/admin/movelogs;
SQL> Rem
SQL> Rem $Header: movelogs.sql 19-jan-2006.00:23:11 banand Exp $
SQL> Rem
SQL> Rem movelogs.sql
SQL> Rem
SQL> Rem Copyright (c) 2006, Oracle. All rights reserved.
SQL> Rem
SQL> Rem NAME
SQL> Rem movelogs.sql - move online logs to new Flash Recovery Area
SQL> Rem
SQL> Rem DESCRIPTION
SQL> Rem This script can be used to move online logs from old online
log
SQL> Rem location to Flash Recovery Area. It assumes that the database
SQL> Rem instance is started with new Flash Recovery Area location.
SQL> Rem
SQL> Rem NOTES
SQL> Rem For use to rename online logs after moving Flash Recovery
Area.
SQL> Rem The script can be executed using following command
SQL> Rem sqlplus '/ as sysdba' @movelogs.sql
SQL> Rem
SQL> Rem MODIFIED (MM/DD/YY)
SQL> Rem banand 01/19/06 - Created
SQL> Rem
SQL>
SQL> SET ECHO ON
SQL> SET FEEDBACK 1
SQL> SET NUMWIDTH 10
SQL> SET LINESIZE 80
SQL> SET TRIMSPOOL ON
SQL> SET TAB OFF
SQL> SET PAGESIZE 100
SQL> declare
2 cursor rlc is
3 select group# grp, thread# thr, bytes/1024 bytes_k
4 from v$log
5 order by 1;
6 stmt varchar2(2048);
7 swtstmt varchar2(1024) := 'alter system switch logfile';
8 ckpstmt varchar2(1024) := 'alter system checkpoint global';
9 begin
10 for rlcRec in rlc loop
11 stmt := 'alter database add logfile thread ' ||
12 rlcRec.thr || ' size ' ||
13 rlcRec.bytes_k || 'K';
14 execute immediate stmt;
15 begin
16 stmt := 'alter database drop logfile group ' || rlcRec.grp;
17 execute immediate stmt;
18 exception
19 when others then
20 execute immediate swtstmt;
21 execute immediate ckpstmt;
22 execute immediate stmt;
23 end;
24 execute immediate swtstmt;
25 end loop;
26 end;
27 /
declare
ERROR at line 1:
ORA-00349: failure obtaining block size for '+Z'
ORA-06512: at line 14
Can someone point me in the right direction as to what I may be doing wrong here - Thank you!

888442 wrote:
I am trying to drop and recreate ONLINE redo logs on my STANDB DATABASE (11.1.0.7)., but i am getting the below error.
On primary, we have done the changes., ie we added new logfile with bigger size and 3 members. When trying to do the same on Standby we are getting this error.
Our database is in Active DG Read only mode and the oracle version is 11.1.0.7.
I have deffered the log apply and cancelled the managed recovery, and dg is in manual mode.
SQL> alter database Add LOGFILE GROUP 4 ('+DT_DG1','+DT_DG2','+DT_DG3') SIZE 1024M;
alter database Add LOGFILE GROUP 4 ('+DT_DG1','+DT_DG2','+DT_DG3') SIZE 1024M
ERROR at line 1:
ORA-00349: failure obtaining block size for '+DT_DG1'First why you are dropping & recreating online redo log files on standby.
On standby only standby redo log files will be used. Not sure what you are trying to do.
here is example how to create online redo log files, Check that diskgroup is mounted and have sufficient space to create.
sys@ORCL> select member from v$logfile;
MEMBER
C:\ORACLE\ORADATA\ORCL\REDO03.LOG
C:\ORACLE\ORADATA\ORCL\REDO02.LOG
C:\ORACLE\ORADATA\ORCL\REDO01.LOG
sys@ORCL> alter database add logfile group 4 (
2     'C:\ORACLE\ORADATA\ORCL\redo_g01a.log',
3     'C:\ORACLE\ORADATA\ORCL\redo_g01b.log',
4     'C:\ORACLE\ORADATA\ORCL\redo_g01c.log') size 10m;
Database altered.
sys@ORCL> select member from v$logfile;
MEMBER
C:\ORACLE\ORADATA\ORCL\REDO03.LOG
C:\ORACLE\ORADATA\ORCL\REDO02.LOG
C:\ORACLE\ORADATA\ORCL\REDO01.LOG
C:\ORACLE\ORADATA\ORCL\REDO_G01A.LOG
C:\ORACLE\ORADATA\ORCL\REDO_G01B.LOG
C:\ORACLE\ORADATA\ORCL\REDO_G01C.LOG
6 rows selected.
sys@ORCL>
Your profile:-
888442
     Newbie
Handle:      888442
Status Level:      Newbie
Registered:      Sep 29, 2011
Total Posts:      12
Total Questions:      8 (7 unresolved)
Close the threads if answered, Keep the forum clean.

Tablespaces and block size in Data Warehouse

We are preparing to implement Data Warehouse on Oracle 11g R2 and currently I am trying to set up some storage strategy - unfortunately I have very little experience with that. The question is what are general advices in such considerations according table spaces and block size? I made some research and it is hard to find some clear answer, there are resources advising that block size is not important and can be left small (8 KB), others state that it is crucial and should be the biggest possible (64KB). The other thing is what part of data should be placed where? Many resources state that keeping indexes apart from its data is a myth and a bad practice as it may lead to decrease of performance, others say that although there is no performance benefit, index table spaces do not need to be backed up and thats why it should be split. The next idea is to have separate table spaces for big tables, small tables, tables accessed frequently and infrequently. How should I organize partitions in terms of table spaces? Is it a good idea to have "old" data (read only) partitions on separate table spaces?
Any help highly appreciated and thank you in advance.

Wojtus-J wrote:
We are preparing to implement Data Warehouse on Oracle 11g R2 and currently I am trying to set up some storage strategy - unfortunately I have very little experience with that. With little experience, the key feature is to avoid big mistakes - don't try to get too clever.
The question is what are general advices in such considerations according table spaces and block size? If you need to ask about block sizes, use the default (i.e. 8KB).
I made some research and it is hard to find some clear answer, But if you get contradictory advice from this forum, how would you decide which bits to follow ?
A couple of sensible guidelines when researching on the internet - look for material that is datestamped with recent dates (last couple of years), or references recent - or at least relevant - versions of Oracle. Give preference to material that explains WHY an idea might be relevant, give greater preference to material that DEMONSTRATES why an idea might be relevant. Check that any explanations and demonstrations are relevant to your planned setup.
The other thing is what part of data should be placed where? Many resources state that keeping indexes apart from its data is a myth and a bad practice as it may lead to decrease of performance, others say that although there is no performance benefit, index table spaces do not need to be backed up and thats why it should be split. The next idea is to have separate table spaces for big tables, small tables, tables accessed frequently and infrequently. How should I organize partitions in terms of table spaces? Is it a good idea to have "old" data (read only) partitions on separate table spaces?
It is often convenient, and sometimes very important, to separate data into different tablespaces based on some aspect of functionality. The performance thing was mooted (badly) in an era when discs were small and (disk) partitions were hard; but all your other examples of why to split are potentially valid for administrative. Big/Small, table/index, old/new, read-only/read-write, fact/dimension etc.
For data warehouses a fairly common practice is to identify some sort of aging pattern for the data, and try to pick a boundary that allows you to partition data so that a large fraction of the data can eventually be made read-only: using tablespaces to mark time-boundaries can be a great convenience - note that the tablespace boundary need not match the partition boudary - e.g. daily partitions in a monthly tablespace. If you take this type of approach, you might have a "working" tablespace for recent data, and then copy the older data to "time-specific" tablespace, packing it and making it readonly as you do so.
Tablespaces are (broadly speaking) about strategy, not performance. (Temporary tablespaces / tablespace groups are probably the exception to this thought.)
Regards
Jonathan Lewis

Mirrored RAID: MediaKit reports block size error

I am trying to create a 2nd set up backup drives for my photos. I have two new iomega 2TB drives, which look essentially identical to drives I'm currently using as my primary backups as a mirrored RAID set.
I can start the process with freshly erased and reformatted drives (with the default mac format, extended, journaled, unencrypted, not case-sensitive). And after a minute or three, I see
"MediaKit reports block size error, usually caused by not being a multiple of 512."
The RAID options are Mirrored RAID, Mac extended journaled, and options settings are default.
I see several series of posts with complaints about encrypting RAIDs and disk block sizes, but not unencrypted errors. I actually started out trying to do this with the 2006 MBP running 10.6.8 and got a different error: "POSIX reports: the operation couldn't be completed. Operation not permitted." I wasn't sure whether the 2TB RAID I already have was set up iwth the older or newer computer--it was definitely before I put Lion on this one--so I tried this one and now have a different error.
Any idea what the problem might be?

Update: I spent some time on the phone with an Apple support RAID expert, and couldn't figure out what the error was; we couldn't bypass it by playing with partitions on the drives, or any of another couple of manuevers that I've already forgotten. He noted that his own searches were showing a lot of mentions of similar problems but only with Iomega drives, and he was finding the same links I found earlier about problems creating encrypted drives. Now trying to decide if it's worth throwing more good money after bad for a call with Iomega support, and waiting to see if the iomega forum is at all helpful.

How to know the OS block size ?

Hi all
I want to know how to get the OS block size of my server ?
For example if my server is Windows 2000 Professionnal , how can I get the size of my OS block size ?
Thank you

One way to find is to right click the drive in Windows Explorer and click Format (Not actually formatting it).
In the popup window, you would see the "Allocation unit size" for the selected drive. Click "Close" to exit when done.

Help please! [using Runtime.exec() to run find command in UNIX]

Hi guys! im trying to use exec() to run the UNIX find command
that my application uses. As you can see from my sample code, the find command finds all files ending with html in my home directory. Unfortunately when I run the program it doesn't give me an output, but when I run it on the shell in the same directory as this code is saved, it works perfectly fine.
Could someone please help me on this one. Many thanks! =)
import java.io.*;
import java.lang.String;
public class RunCommand {
        public static void main(String[] args) {
                try {
                        String[] command = {"find", "~/", "-name",
                                        "*.html", "-print"};
                        String find_str;
                        Process find_proc = Runtime.getRuntime().exec(
                                        command);
                        DataInputStream find_in = new DataInputStream(
                                        find_proc.getInputStream());
                        try {
                                while ((find_str = find_in.readLine())
                                                                != null) {
                                        System.out.println(find_str);
                        } catch (IOException e) {
                                System.exit(0);
                } catch (IOException e1) {
                        System.err.println(e1);
                        System.exit(1);
                System.exit(0);
}

I don't see anythi obvious. In both catch blocks, call printSckTrace on the exception yhou caught.
I think the real culprit is the ~ though.
~ is interpreted by some (most?) shells to men home dir. However, when you just exec a command, you don't have a shell to do that interpretation for you, so it's looking for a directory that's literally named ~.
Either exec a shell (read the man pages for the shell of your choice, but for zsh I think it's "/bin/zsh -c find ~ blah blah blah) or else just put the actual path to your home directory into the string you pass to exec. You can get that from System.getProperty("user.home").

What USB storage devices have a block size of 512 bytes?

After pulling my hair out for weeks trying to get a usb hard drive to work with my new AirPort Extreme (802.11n), I ran across this
http://docs.info.apple.com/article.html?artnum=305038
AirPort Extreme (802.11n): USB storage device supported formats and protocols
You can connect USB-based storage devices to an AirPort Extreme (802.11n). Learn which formats and protocols are supported.
The AirPort Extreme (802.11n) supports USB storage devices that have a block size of 512 bytes, and are formatted as Mac OS Extended (HFS-plus), FAT16, or FAT32. Not all USB storage devices use a block size of 512 bytes.
The AirPort Extreme (802.11n) shares storage devices based on the format used to initialize the storage device. For example, if HFS-plus formatting was used, AFP and SMB/CIFS protocols are used to share the device on the network. If FAT16 or FAT32 was used, SMB/CIFS protocols are used.
The AirPort Extreme (802.11n) works with disks that have a single partition and are not software RAID volumes (no more than one volume per physical disk). If the disk is a self-contained RAID that presents itself to a computer as a single volume requiring no software support, then it is supported.
Note: Use AirPort Disk Utility to discover and mount AirPort Extreme-based volumes over the network.
Now, this information is not easily obtainable while
shopping for a new usb hard drive. How do I find out which
ones support this 512 byte block size????
Would have bee nice to know that not all usb hard drives
are supported by the AirPort Extreme (802.11n) before I
purchased it.
Thanks
J Riley

Duane posted a link to an unofficial 802.11n Airport Extreme Hard Drive Compatibility List.
http://www.ifelix.co.uk/tech/8014.html
Still not enough information to make an informed purchase that
will work.

Recommended Block Size For RAID 0

I am setting up a RAID configuration (Striping, no Parity, Mac G5, OS-X) and was curious what the recommended Block Size should be. Content is primarily (but not limited to) Images created with Adobe Photoshop CS2 and range in size from 1.5MB to >20MB. The default for OS-X is 32K chunks of data.
Drives are External FW-400.
Many thanks, and Happy Holidays to all!

If it is just scratch, run some benchmarks with it set to 128k and 256k and see how it feels with each. The default is too small, though some find it acceptable for small images. For larger files you want larger - and for PS scratch you definitely want 128 or 256k.

OS Block Size finding command

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