Bug 32819
Summary: | unnecessary add swap during upgrade | ||
---|---|---|---|
Product: | [Retired] Red Hat Linux | Reporter: | Gene Czarcinski <gczarcinski> |
Component: | anaconda | Assignee: | Brent Fox <bfox> |
Status: | CLOSED NOTABUG | QA Contact: | Brock Organ <borgan> |
Severity: | medium | Docs Contact: | |
Priority: | medium | ||
Version: | 7.1 | ||
Target Milestone: | --- | ||
Target Release: | --- | ||
Hardware: | i386 | ||
OS: | Linux | ||
Whiteboard: | |||
Fixed In Version: | Doc Type: | Bug Fix | |
Doc Text: | Story Points: | --- | |
Clone Of: | Environment: | ||
Last Closed: | 2001-03-23 18:18:18 UTC | Type: | --- |
Regression: | --- | Mount Type: | --- |
Documentation: | --- | CRM: | |
Verified Versions: | Category: | --- | |
oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
Cloudforms Team: | --- | Target Upstream Version: | |
Embargoed: |
Description
Gene Czarcinski
2001-03-23 14:46:20 UTC
Brent please look at. The 2.4 kernel needs twice as much swap space as the amount of RAM. So, if you have 384 MB of RAM, then you need (384 * 2) = 768 MB of swap. Since you already have 517 MB of swap, adding a 251 MB swap file will give you 768 MB of RAM, so the calculations are correct. At some point, however, the 2x swap rule starts to become excessive. If someone has a web server with 4 Gigs of RAM, we shouldn't require 8 Gigs of swap. So, we applied some rules to the upgrade process. If the user has less than 500MB of RAM, then we try to make a swap file that will give them twice as much swap as RAM. If they have more RAM than that, then we skip the swap file screen. OK, your explanation sounds reasonable. However, 1. Why stop at 500M of ram? Why not warn folks anyway even if you don't suggest a 2*2GB? 2. This only happens on upgrade. If you believe it is needed for upgrade, then it should apply to a fresh install also (which with my testing it does not). 3. Why a swap file rather than a swap partition? 4. The implication in the current screen is that the upgrade will not work because the kernel/anaconda will fail. It now appears to me that you are referring to the installed system. For the above reasons, I am reopening this bug. If it is closed NOTABUG, so be it but you should consider the above (at least for 7.2 if not 7.1). I'll try to answer your questions as best I can. 1. We feel that requiring over 1 GB of swap is unnecessary. A warning would be nice and that's something we're considering. 2. The problem is upgrades take more memory (and thus more swap) than a regular install. For an upgrade, the installer has to query the RPM database on the installed system and then compare it to the new package list. We were seeing some problems internally with the kernel running out of memory during upgrades and would cause the installer to crash. 3. Since the problem manifests itself most severely during upgrades, swap files were the way to go because most drives are fully partitioned. We don't currently have the ability to modify existing partitions to make room for a new swap partition, so swap files were our only choice. 4. The problem is not as severe on an installed system, but it still exists. What I mean is that if the 2.4 kernel doesn't have enough swap space, you will see decreased performance on an installed system. That's why we leave the swap file on the disk after upgrading. We are aware that this isn't the ideal solution to the problem, but there are some inherent difficulties with upgrading a machine from a 2.2 based kernel to a 2.4 based kernel. I hope this addresses your concerns. I mean, these are issues that we've thought about, and we've come up with what we think is an acceptable solution. OK, lets close this out. Gene |