5.20.UC1 AIX 4.3.3: Max Chunks
The poster asked how to work out the maximum number of chunks allowed in OnLine 5.20.UC1 on AIX 4.3.3, given the length of the chunk pathnames. Answers explained that the limit comes from fitting chunk entries on a single page: Jonathan Leffler gave a rough formula (page size, 4K on AIX, divided by name length plus overhead) and pointed to the OnLine 5 Administrator's Guide. Art Kagel added the practical detail: the official max is 64 chunks (really 63), each entry costing 28 bytes plus a 4-byte slot, so e.g. 4-7 character paths allow 56 chunks, 8-11 characters 50, and names divisible by 4 cost an extra 4 bytes.
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Does any happen to have written a routine or have a easy-to-follow (smile) procedure that will enable me to determine the maximum number of chunks I can assign, given that I know the number of characters each pathway assignments will be in the future? Thanks in advance.Clifton _______________________________________________ Join Excite! - http://www.excite.com The most personalized portal on the Web!
On 3/23/06, clifbean@ex.... <clifbean@excite.com> wrote: > Does any happen to have written a routine or have a easy-to-follow (smile) > procedure that will enable me to determine the maximum number of chunks I can > assign, given that I know the number of characters each pathway assignments > will be in the future? Thanks in advance.Clifton WHICH VERSION? Everybody (not just Clifton) is asking questions and forgetting to mention version!!! IDS 10; 32,767 chunks. Did you need any more than that? Actually, there's an outside chance that number is wrong and its only 4095, some other power of two minus one up in the multiple thousands range; is that too few for you? If you're asking about a different version - please say so. -- Jonathan Leffler #include <disclaimer.h> Email: jleffler@earthlink.net, jleffler@us.ibm.com Guardian of DBD::Informix v2005.02 -- http://dbi.perl.org/
Check the subject line... ;-) = "Jonathan Le...." = <jleffler.iiug@gm = ail.com> = To Sent by: ids@iiug.org = ids-bounces@iiug. = cc org = Subj= ect Re: 5.20.UC1 AIX 4.3.3: Max Chun= ks 03/23/2006 07:22 [6536] = PM = = = Please respond to = ids@iiug.org = = = On 3/23/06, clifbean@ex.... <clifbean@excite.com> wrote: > Does any happen to have written a routine or have a easy-to-follow (smile) > procedure that will enable me to determine the maximum number of chun= ks I can > assign, given that I know the number of characters each pathway assignments > will be in the future? Thanks in advance.Clifton WHICH VERSION? Everybody (not just Clifton) is asking questions and forgetting to mention version!!! IDS 10; 32,767 chunks. Did you need any more than that? Actually, there's an outside chance that number is wrong and its only 4095, some other power of two minus one up in the multiple thousands range; is that too few for you? If you're asking about a different version - please say so. -- Jonathan Leffler #include <disclaimer.h> Email: jleffler@earthlink.net, jleffler@us.ibm.com Guardian of DBD::Informix v2005.02 -- http://dbi.perl.org/ ***********************************************************************= ******** Forum Note: Use "Reply" to post a response in the discussion forum. =
Red face - ooops!!!! On 3/23/06, Jonathan Le.... <jleffler.iiug@gmail.com> wrote: > > On 3/23/06, clifbean@ex.... <clifbean@excite.com> wrote: > > Does any happen to have written a routine or have a easy-to-follow (smile) > > procedure that will enable me to determine the maximum number of chunks I > can > > assign, given that I know the number of characters each pathway assignments > > will be in the future? Thanks in advance.Clifton > > WHICH VERSION? Next time, I'll read the subject line - though repeating the version in the body of the message isn't a bad idea. I apologize, Clifton. Other people had been not saying which version - you are excused. > Everybody (not just Clifton) is asking questions and forgetting to > mention version!!! > > IDS 10; 32,767 chunks. Did you need any more than that? > > Actually, there's an outside chance that number is wrong and its only > 4095, some other power of two minus one up in the multiple thousands > range; is that too few for you? > > If you're asking about a different version - please say so. You'r easking about a different version - OnLine 5.20. OK - IIRC, you're limited to the number of chunk device names that fit on a single page. So, if your names are long (like /usr/informix/online-5.20/dev/servername.rootdbs.p0) you won't be able to get many chunks to the system; if your names are short (like /ix/x32), you'll be able to fit a lot more on a page and hence get more chunks to the system. I don't remember what the constant overhead term is - probably 6-12 bytes (so if your file names are N bytes long, you can fit M = (2048 - 28) / (N + [6..12]) chunks on the page. Check in the OnLine 5 Admins Guide and Ref - it was really good and detailed. -- Jonathan Leffler #include <disclaimer.h> Email: jleffler@earthlink.net, jleffler@us.ibm.com Guardian of DBD::Informix v2005.02 -- http://dbi.perl.org/
On 3/23/06, Jonathan Le.... <jleffler.iiug@gmail.com> wrote: > > Red face - ooops!!!! > > On 3/23/06, Jonathan Le.... <jleffler.iiug@gmail.com> wrote: > > > > On 3/23/06, clifbean@ex.... <clifbean@excite.com> wrote: > > > Does any happen to have written a routine or have a easy-to-follow (smile) > > > procedure that will enable me to determine the maximum number of chunks I > > can > > > assign, given that I know the number of characters each pathway > assignments > > > will be in the future? Thanks in advance.Clifton > > > > WHICH VERSION? > > Next time, I'll read the subject line - though repeating the version > in the body of the message isn't a bad idea. > > I apologize, Clifton. > > Other people had been not saying which version - you are excused. > > > Everybody (not just Clifton) is asking questions and forgetting to > > mention version!!! > > > > IDS 10; 32,767 chunks. Did you need any more than that? > > > > Actually, there's an outside chance that number is wrong and its only > > 4095, some other power of two minus one up in the multiple thousands > > range; is that too few for you? > > > > If you're asking about a different version - please say so. > > You'r easking about a different version - OnLine 5.20. > > OK - IIRC, you're limited to the number of chunk device names that fit > on a single page. > > So, if your names are long (like > /usr/informix/online-5.20/dev/servername.rootdbs.p0) you won't be able > to get many chunks to the system; if your names are short (like > /ix/x32), you'll be able to fit a lot more on a page and hence get > more chunks to the system. I don't remember what the constant > overhead term is - probably 6-12 bytes (so if your file names are N > bytes long, you can fit M = (2048 - 28) / (N + [6..12]) chunks on the > page. > > Check in the OnLine 5 Admins Guide and Ref - it was really good and detailed. AIX probably has a 4K page size - sub 4096 where I wrote 2048 :-( -- Jonathan Leffler #include <disclaimer.h> Email: jleffler@earthlink.net, jleffler@us.ibm.com Guardian of DBD::Informix v2005.02 -- http://dbi.perl.org/
Yes it does (have a 4k page size) Keith -----Original Message----- From: Jonathan Le.... [mailto:jleffler.iiug@gmail.com] Sent: Friday, March 24, 2006 2:45 AM To: ids@iiug.org Subject: Re: 5.20.UC1 AIX 4.3.3: Max Chunks [6539] On 3/23/06, Jonathan Le.... <jleffler.iiug@gmail.com> wrote: > > Red face - ooops!!!! > > On 3/23/06, Jonathan Le.... <jleffler.iiug@gmail.com> wrote: > > > > On 3/23/06, clifbean@ex.... <clifbean@excite.com> wrote: > > > Does any happen to have written a routine or have a easy-to-follow (smile) > > > procedure that will enable me to determine the maximum number of chunks I > > can > > > assign, given that I know the number of characters each pathway > assignments > > > will be in the future? Thanks in advance.Clifton > > > > WHICH VERSION? > > Next time, I'll read the subject line - though repeating the version > in the body of the message isn't a bad idea. > > I apologize, Clifton. > > Other people had been not saying which version - you are excused. > > > Everybody (not just Clifton) is asking questions and forgetting to > > mention version!!! > > > > IDS 10; 32,767 chunks. Did you need any more than that? > > > > Actually, there's an outside chance that number is wrong and its only > > 4095, some other power of two minus one up in the multiple thousands > > range; is that too few for you? > > > > If you're asking about a different version - please say so. > > You'r easking about a different version - OnLine 5.20. > > OK - IIRC, you're limited to the number of chunk device names that fit > on a single page. > > So, if your names are long (like > /usr/informix/online-5.20/dev/servername.rootdbs.p0) you won't be able > to get many chunks to the system; if your names are short (like > /ix/x32), you'll be able to fit a lot more on a page and hence get > more chunks to the system. I don't remember what the constant > overhead term is - probably 6-12 bytes (so if your file names are N > bytes long, you can fit M = (2048 - 28) / (N + [6..12]) chunks on the > page. > > Check in the OnLine 5 Admins Guide and Ref - it was really good and detailed. AIX probably has a 4K page size - sub 4096 where I wrote 2048 :-( -- Jonathan Leffler #include <disclaimer.h> Email: jleffler@earthlink.net, jleffler@us.ibm.com Guardian of DBD::Informix v2005.02 -- http://dbi.perl.org/ ******************************************************************************* Forum Note: Use "Reply" to post a response in the discussion forum. ******************************************************************************** ** This message is sent in strict confidence for the addressee only. It may contain legally privileged information. The contents are not to be disclosed to anyone other than the addressee. Unauthorised recipients are requested to preserve this confidentiality and to advise the sender immediately of any error in transmission. This footnote also confirms that this email message has been swept for the presence of computer viruses, however we cannot guarantee that this message is free from such problems. ******************************************************************************** **
Jonathan Le.... said: > > On 3/23/06, clifbean@ex.... <clifbean@excite.com> wrote: >> Does any happen to have written a routine or have a easy-to-follow >> (smile) >> procedure that will enable me to determine the maximum number of chunks >> I > can >> assign, given that I know the number of characters each pathway >> assignments >> will be in the future? Thanks in advance.Clifton > > WHICH VERSION? From the subject ("Re: 5.20.UC1 AIX 4.3.3"), I'm guessing that he wants to know about IDS 7.23.UC2 on Solaris 8. -- Bye now, Obnoxio Information within this post contains forward looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21B of the S E C Act of 1934. Statements that involve discussions with respect to projections of future events are not statements of historical fact and may be forward looking statements. Don't rely on them to make a decision. The poster is not a reporting company registered under the Exchange Act of 1934. I have received a life peerage from Her Majesty, who is not an officer, minister or affiliate Labour party member. I intend to recover my loan now, which could cause the parliamentary majority to go down, resulting in losses for you. Today's Labour party has: an accumulated deficit and a reliance on loans from officers and affiliates to pay expenses. It is not an operating political party. The party is going to need financing to continue as a going concern. A failure to finance could cause the party to go out of business. This report shall not be construed as any kind of investment advice or solicitation. You can lose all your money by investing in this party.
The official max #chunks in 5.xx is 64, however, the chunknames have to be 3 characters or less to get that and in actuality you only get 63 as the entry's minimum size is 28bytes plus 4 for the slot entry. Of course that means all your chunks have to live in root and have two character names (/c1) or live in the startup directory and have only three char names. If you use the practical minimum you have to put the chunks (or at least links) in a one character directory off root and then the names can be up to 4 chars long (/d/abcd). Note that if the name length is divisible by 4 IDS adds another 4 bytes to the entry length. With 4 to 7 character chunk paths you get 56 chunks max, 8 to 11 char paths get you 50 chunks, etc. Art S. Kagel ----- Original Message ----- From: Jonathan Le.... <ids@iiug.org> At: 3/23 20:43 Red face - ooops!!!! On 3/23/06, Jonathan Le.... <jleffler.iiug@gmail.com> wrote: > > On 3/23/06, clifbean@ex.... <clifbean@excite.com> wrote: > > Does any happen to have written a routine or have a easy-to-follow (smile) > > procedure that will enable me to determine the maximum number of chunks I > can > > assign, given that I know the number of characters each pathway assignments > > will be in the future? Thanks in advance.Clifton > > WHICH VERSION? Next time, I'll read the subject line - though repeating the version in the body of the message isn't a bad idea. I apologize, Clifton. Other people had been not saying which version - you are excused. > Everybody (not just Clifton) is asking questions and forgetting to > mention version!!! > > IDS 10; 32,767 chunks. Did you need any more than that? > > Actually, there's an outside chance that number is wrong and its only > 4095, some other power of two minus one up in the multiple thousands > range; is that too few for you? > > If you're asking about a different version - please say so. You'r easking about a different version - OnLine 5.20. OK - IIRC, you're limited to the number of chunk device names that fit on a single page. So, if your names are long (like /usr/informix/online-5.20/dev/servername.rootdbs.p0) you won't be able to get many chunks to the system; if your names are short (like /ix/x32), you'll be able to fit a lot more on a page and hence get more chunks to the system. I don't remember what the constant overhead term is - probably 6-12 bytes (so if your file names are N bytes long, you can fit M = (2048 - 28) / (N + [6..12]) chunks on the page. Check in the OnLine 5 Admins Guide and Ref - it was really good and detailed. -- Jonathan Leffler #include <disclaimer.h> Email: jleffler@earthlink.net, jleffler@us.ibm.com Guardian of DBD::Informix v2005.02 -- http://dbi.perl.org/ ******************************************************************************* Forum Note: Use "Reply" to post a response in the discussion forum.