-----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Bob Shannon Sent: 26 November, 2014 17:20 To: [email protected] Subject: Re: VLF caching
>>VLF writes SMF 41 records, but they are unusable for LLA. >That is not correct. It is true that LLA does know what it put into the cache >(as would most VLF exploiters), but (as with all VLF exploiters) it has no >idea what VLF has taken out due to trimming. I tend to agree with the OP. LLA will only check VLF for modules it previously cached. Granted there may be some trimming, but I don't ever recall seeing less than a 100% hit ratio for LLA. The other VLF exploiters behave differently and the SMF statistics for them tend to be helpful. The CSVLLIX1 exit is required for accurate LLA fetch statistics. Bob Shannon Rocket Software ---- Correct, that is why you also see Deletes in the LLA VLF cache. If LLA has a module that qualifies for the cache, it can delete a module that does not qualify anymore to make room for the new one. Therefor you will see deletes and adds of modules caused by LLA management of the cache, and hardly any trims caused by VLF management of the cache. The other exploiters push 'everything' into the cache and will find out later if the object is still there. VLF hitratio and trim statistics are indeed useful here. Kees. ******************************************************** For information, services and offers, please visit our web site: http://www.klm.com. This e-mail and any attachment may contain confidential and privileged material intended for the addressee only. If you are not the addressee, you are notified that no part of the e-mail or any attachment may be disclosed, copied or distributed, and that any other action related to this e-mail or attachment is strictly prohibited, and may be unlawful. If you have received this e-mail by error, please notify the sender immediately by return e-mail, and delete this message. Koninklijke Luchtvaart Maatschappij NV (KLM), its subsidiaries and/or its employees shall not be liable for the incorrect or incomplete transmission of this e-mail or any attachments, nor responsible for any delay in receipt. Koninklijke Luchtvaart Maatschappij N.V. (also known as KLM Royal Dutch Airlines) is registered in Amstelveen, The Netherlands, with registered number 33014286 ******************************************************** ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
