So IOPS is not the right way of measuring for mainframe data So there is a big difference between IOPS and Response time
On Sun, 8 Sept 2024, 16:37 Nigel Morton, < [email protected]> wrote: > IOPS means I/Os per second so it's a measure of the throughput of the > devices. In practice, with z/OS you won't generate anywhere near the > maximum IOPs for a modern all-flash storage device. IMHO response time is a > more useful measure for performance especially as IOPs figures will > probably come from synthetic benchmarks. > > Also consider how you'll migrate from an old storage system to a new one. > Copy services functions such as multi-target metro mirror are excellent but > will almost certainly require that the source and target vendor are the > same. You might also need to consider what type of FICON adapters can > coexist with your FICON switches and channels. > > On Sun, 8 Sept 2024 at 05:04, Peter < > [email protected]> wrote: > > > Hello > > > > > > I have seen a term called IOPS in the technical sheet > > > > > > > > From the storage perspective what does IOPS do? How does that influence > on > > storage solution selection? > > > > On Thu, 5 Sept 2024, 16:03 Radoslaw Skorupka, < > > [email protected]> wrote: > > > > > Cache - the more the better. Obvious. However there are different ways > > > of use of DRAM as a cache. > > > Some vendors have cache mirrored. Others don't mirror READ cache. > > > Usually the same memory is used for other purposes, not only for > caching > > > READs and WRITEs. So, "1TB of cache" is not simply comparable between > > > vendors. > > > > > > Disk module. SSD or magnetic? Usually SSD nowadays. But which SSD? > There > > > are many flavours and capacities. > > > Usually smaller modules gives better overall performance. And better > > > flexibility. And there are faster and slower modules. > > > > > > Remote copy. > > > Do you want to perform PiT copy on secondary/slave? > > > Do you want asynchronous copy? > > > Do you want PPRC and FLASHCOPY command compatibility? > > > What QoS features of PiT and Remote Copy do you want? > > > etc. > > > > > > > > > -- > > > Radoslaw Skorupka > > > Lodz, Poland > > > > > > > > > > > > > > > W dniu 04.09.2024 o 20:27, Peter pisze: > > > > Thanks for the inputs > > > > > > > > Currently we are metro mirrored. > > > > > > > > So I believe I also need to look into their quality of support? > > > > > > > > Cache and modules? - what exactly I need to be researching on this ? > > > > > > > > On Wed, 4 Sept 2024, 19:40 Radoslaw Skorupka, < > > > > [email protected]> wrote: > > > > > > > >> W dniu 04.09.2024 o 10:52, Peter pisze: > > > >>> Hello, > > > >>> > > > >>> I Must confess that I am not a Storage expert. In our organization > > we > > > >> are > > > >>> working on procuring a new storage box solution. I have been asked > to > > > >>> study and give an opinion on which solution would be perfect for > our > > > >>> mainframe environment. > > > >>> > > > >>> Could someone give me your advise based on your experience. When > > > >> selecting > > > >>> a new storage solution what are the important points that needs to > be > > > >>> looked into the vendors proposal ? > > > >> Generally speaking a DASD box is not just a bunch of disks. It is > DASD > > > >> space + performance + embedded software. > > > >> > > > >> DASD space - obvious > > > >> > > > >> performance - a little bit more complex. There is no single number, > > like > > > >> car velocity. Even cache size should be understood, because vendors > > have > > > >> different way of use of it. Two approaches: compare "guts" (cache, > > disk > > > >> modules, etc.) or compare benchmarks. > > > >> > > > >> embedded software - remote copy, point in time copy, some "obvious" > > > >> things like SuperPAV, etc. Unless you have specific requirements all > > > >> vendors apply. However their offering differ and it could be > > important. > > > >> And features like Safeguarded copy. > > > >> > > > >> ...and zHyperlink. All vendors have FICON32 nowadays, and AFAIK all > do > > > >> have zHyperlink. > > > >> > > > >> > > > >> HTH > > > >> > > > >> -- > > > >> Radoslaw Skorupka > > > >> Lodz, Poland > > > >> > > > >> > > > > > > ---------------------------------------------------------------------- > > > For IBM-MAIN subscribe / signoff / archive access instructions, > > > send email to [email protected] with the message: INFO IBM-MAIN > > > > > > > ---------------------------------------------------------------------- > > For IBM-MAIN subscribe / signoff / archive access instructions, > > send email to [email protected] with the message: INFO IBM-MAIN > > > > ---------------------------------------------------------------------- > For IBM-MAIN subscribe / signoff / archive access instructions, > send email to [email protected] with the message: INFO IBM-MAIN > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
