When we first tried Linux in an LPAR, about 3 months ago, we were concerned about this. The LPAR we were using was defined for another purpose, and had access to 12,000+ DASD devices. We went to IBM, and they recommended CIO_IGNORE. I tested that under VM, and it appeared to work, but when we tried it in the real LPAR, the kernel couldn't find ANY DASD devices.
Rather than delay the test, we booted without the parm, and it came up fine, 12,000+ devices and all (they were scoped down in the module parm). It took about 5 minutes to scan them all on our z9 with Ficon. We haven't tried Linux in an LPAR again since, so I have no way to determine what went wrong. -----Original Message----- From: Linux on 390 Port [mailto:[EMAIL PROTECTED] On Behalf Of David Boyes Sent: Thursday, August 02, 2007 9:41 AM To: [email protected] Subject: Re: [LINUX-390] Defining an LPAR on a z box to run LINUX > > > You should also use cio_ignore= to ignore all devices you might want > > to > > > use later but not now. The major issue (besides regulating access) is > > > not IPL time (though applications like HAL are extremely slow to start > > > with many devices) > > > > Can be order of 45-50 minutes with 16K devices. > > Ugh. Do you know what takes so long (HAL?) FWIW, in-kernel detection of > devices is now done in max. 30 seconds due to parallelism (unlike 2.4, > which literally may take hours if some devices behave badly). Seems to spend most of it's time figuring out what kind of device it is. As you say, newer versions are faster. I prefer to see it as another compelling reason to run z/VM and not mess with Linux in LPARs. 8-) > But nevertheless: Know how to use cio_ignore= :) Indeed. ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 -------------------------------------------------------- This message w/attachments (message) may be privileged, confidential or proprietary, and if you are not an intended recipient, please notify the sender, do not use or share it and delete it. Unless specifically indicated, this message is not an offer to sell or a solicitation of any investment products or other financial product or service, an official confirmation of any transaction, or an official statement of Merrill Lynch. Subject to applicable law, Merrill Lynch may monitor, review and retain e-communications (EC) traveling through its networks/systems. The laws of the country of each sender/recipient may impact the handling of EC, and EC may be archived, supervised and produced in countries other than the country in which you are located. This message cannot be guaranteed to be secure or error-free. This message is subject to terms available at the following link: http://www.ml.com/e-communications_terms/. By messaging with Merrill Lynch you consent to the foregoing. -------------------------------------------------------- ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
