Space free , sysmaster and onstat_d output are different !!!!!

Hi on 11.70.FC8 (i know i have to upgrade , it s ongoing :) ) i calculated the space free with onstat -d and the statement below, but the output are different with onstat -d (free column * page size), each dbspace has different pagesize and on sysmaster database sysmaster;select name[1,8] dbspace, -- name truncated to fit on one line round(sum(chksize * d.pagesize), 2) Total_size, -- sum of all chuncks size pages round(sum(nfree * d.pagesize),2) Space_Free, round (100 - (sum(nfree)) / (sum(chksize)) * 100, 2) percent_Used from sysdbspaces d, syschunks c where d.dbsnum = c.dbsnum and d.is_blobspace = 0 and d.is_sbspace = 0 group by 1; does anyone faced it before ? Thanks :) ------------------------------ John Smith ------------------------------ #Informix

For regular dbspaces (as you are limiting the query to), syschunk.nfree & chksize are in units of the system default page size (sysshmvals.sh_pagesize) and not the dbspace page size. It's a bit confusing when comparing against onstat -d. ------------------------------ Mike Walker ------------------------------

But in my case, sh_pagesize is the same as pagesize !! sh_pagesize 4096 ------------------------------ John Smith ------------------------------

You said that each dbspace has a different pagesize... Is it wrong for ALL dbspaces? Do you have some dbspaces with names greater than 8 characters which are being grouped together? ------------------------------ Mike Walker ------------------------------

Here is a copy of my notes in my dbspace.ec utility about page size in syschunks: /* The semantics of syschunks and page sizes changes from version to version: < v10 V10 v11.10/11.50 v11.70+ ------- ------------ ---------------- --------------- chksize # pages # pages # default pages # default pages pagesize DNA # def pgs/pg # bytes/page # bytes/page nfree # pages # def pages # def pages dbspace: # def pages blbspc: # blb pages sbspace: #sbpages */ So, v11.70 stores the number in nfree is the number of default sized pages (so 4K on MAC, Windows or AIX, 2K everywhere else). So, your free space line: round(sum(nfree * d.pagesize),2) Space_Free, should be: round(sum(nfree * <def pagesize>) Space_Free, You can get that by either selecting the pagesize from the chunk table or querying the sysmaster:sysshmvals.sh_pagesize column (divided by 1024 if you want KB). ------------------------------ Art Kagel ------------------------------

Oh, forgot, you can always just use dbsavail from my utils2_ak package which you can download from my web site at www.askdbmgt.com/my-utilities Art ------------------------------ Art S. Kagel, President and Principal Consultant ASK Database Management Corp. www.askdbmgt.com ------------------------------

Yes, but do i have to the sh_pagesize instead of the each dbspace page size ? ------------------------------ John Smith ------------------------------

Hello Is it wrong for ALL dbspaces? no only for those with a page size different than the default page size (4096, onstat -b) ------------------------------ John Smith ------------------------------

Mr Art it s all right :) , nfree column is number of 4k pages (default) :) thanks a lot ------------------------------ John Smith ------------------------------

Ah, good, you answered your own question. Yes, you always use the default page size for free in the latest releases for regular and temp dbspaces. For blobspaces and smart blobspaces use the space's pagesize instead. Did I mention that you can just use my dbsavail utility? And if you need to get the data into your own application, dbsavail installs stored procedures to handle all of the heavy lifting, so you could just call them. Art Art S. Kagel, President and Principal Consultant ASK Database Management www.askdbmgt.com Blog: http://informix-myview.blogspot.com/ Disclaimer: Please keep in mind that my own opinions are my own opinions and do not reflect on the IIUG, nor any other organization with which I am associated either explicitly, implicitly, or by inference. Neither do those opinions reflect those of other individuals affiliated with any entity with which I am affiliated nor those of the entities themselves.

« The good teacher is the teacher that pushes the pupil to ask himself the good questions and triggers the little thing that makes him start the right reasoning, then answer by himself "

Yup - just what I said: For regular dbspaces (as you are limiting the query to), syschunk.nfree & chksize are in units of the system default page size (sysshmvals.sh_pagesize) and NOT the dbspace page size. :-) ------------------------------ Mike Walker ------------------------------

Hi :) also, please, for having a database size, what about ti_nptotal and ti_npused for tables with ti_pagesize != def pagesize (4096) the values are also in def page size ? or in space pagesize ? and the database contains data in a sbpace , does the sbpace data included with the statement below ? SELECT dbsname, tabname, ti_nptotal, ti_npused, ti_pagesize FROM sysdatabases AS d, systabnames AS n, systabinfo AS i WHERE n.dbsname = d.name AND ti_partnum = n.partnum ------------------------------ John Smith ------------------------------

This one IS in units of the dbspace page size (ti_pagesize). ------------------------------ Mike Walker ------------------------------

Thanks and does it include the data in the SBspace ? ------------------------------ John Smith ------------------------------

i think no :) forget about it :) thank youuuuuuuu :) ------------------------------ John Smith ------------------------------