System Intermittently unresponsive - hangs

[lindycorp]

Since a recent upgrade to Yosemite (at least it seems that way) my iMac has the infuriating problem of intermittent episodes of unresponsiveness. About every 30 seconds or so, it will become completely unresponsive for anywhere from 10-30 seconds, with the infamous spinning beach ball of death. Then the system will "release," and behave normally, until the next episode.

In trying to fix this, I've repaired disc permissions with no luck. I've also discovered that a command-R reboot will not reboot to recovery -- in fact, it just hangs about 30% of the way through the progress bar at the "white screen" -- no matter how long I sit there. Only a hard reboot will recover the machine at that point. Obviously this whole thing has been a deal killer for using the machine, for instance it happened 3 times just while typing this.

I'm on a 27 inch mid 2011 iMac (which I used to love) running OS X version 10.10.2. I use time machine to a 2 Tb Lacie Porsche.

At wits end; any help greatly appreciated.

 

[harryb2448]

G'day and welcome to the forums.

How much memory and how much free space on the hard drive?

When you downloaded Yosemite did you burn it to a USB thumb drive you could boot from to test the hard drive? If so connect, reboot, hold down 'C', and go to Utilities > Disk Utility and run Repair Disk.

 

[Slydude]

I know you mentioned checking disk permissions and that was OK. Did you verify the disk as well and make any suggested repairs?

 

[lindycorp]

Harryb, good questions. Just under 400g free space on the 1 Tb disk in question. After Yosemite installed, I upgraded to 12 gb memory, since it seemed performance was a bit slower, and, after all, it was Christmas My iMac was a *screamer* after that -- sub second performance on everything -- until this thing bit. I did not burn Yosemite to a thumb drive. It does not seem like you get that opportunity. It's more of a "do you want to upgrade your system?" ... and then the download and upgrade takes place all in one step ....

slydude, I ran a verify disk and got: "The volume Macintosh HD appears to be OK" ...

thanx both ...

 

[harryb2448]

Lndy it appears to me all this upgrading does detract a little from performance rather than a format and clean install. One needs to burn Yosemite and others prior to running th Installer.

Do you leave the Lacie connected all the time?

It may be that TM is backing up on an hourly basis and when in this mode may be distracting from your performance. Persoanlly I prefer a cloning system to my external drive and backup when I want to, not TM. Try disconnecting the Lacie and see what happens.

 

[lclev]

I am wondering if the upgrade to 12GB of memory could be the problem? It is possible for an upgrade to work perfectly for a period of time and then have an issue develop.

If It were my system - after I ran the standard set of maintenance and checking procedures - permissions, disk repair, smc, pram, cache clean, I would look for any new app installs - especially ones that run in the background. I would shut down any background apps and ones that load on start up, if any. If all that produced no changes, I would go to hardware upgrades and in this case memory has been upgraded.

I would look at removing part of the memory. I am guessing but if you added to the original apple memory, I would start with reseating the chips. If that does not help I would next take out the new memory and see what happened then swap and put the new in and see what happens. Keep a record of what you are doing so if an issue arises you know what you did.

Unfortunately I haven't found any memory testing programs that work well but if anyone else has a recommendation that might be an idea. I tend to use the swap the chips and try it again method.

Just my thoughts.

Lisa

 

[lindycorp]

Do you leave the Lacie connected all the time? ... It may be that TM is backing up on an hourly basis and when in this mode may be distracting from your performance.

Yes I do, that's kind of the idea behind a backup drive and TM It ran fine that way for 2 years, but I'll try disconnecting it to see what happens, as I am most desperate to find a solution!

 

[harryb2448]

When you have the external connected, go into Disk Utility on the internal drive, select by highlighting and run Repair Disk over it and see what is reported.

 

[lindycorp]

Lisa, thanks for your response.

... - after I ran the standard set of maintenance and checking procedures - permissions, disk repair, smc, pram, cache clean ...

I grinned when I saw your logo, because what you describe here seems to be, while more complicated, also simpler at the same time in Windows, where I feel very confident troubleshooting. I must confess, Macs seem like much more of a "black box." Other than going into Disc Doctor and running a verify/repair disk permissions and a verify disk, what other tools are available to troubleshoot?

Also, it seems to me this may be a bad sector on disc. What is the significance of the system's inability to load recovery from the time machine on a reboot with Cmd-R pressed???

Lastly, in going backwards now, I recall that this problem actually happened to me once before the new memory was installed. I used the "Just Answers" website, and the "help" was clearly just someone googling as I found the same "answers" they did. The person helping me had me reboot a myriad of different ways, and ultimately (after about 4 days of back and forth) told me I was going to need to reinstall Yosemite and everything else, which, didn't seem like a real diagnosis or real attempt at troubleshooting. That's when I discovered that I couldn't reboot or recover from a reboot with command-R.

Anyway, if you have any other tools I may attempt a diagnosis with, or insight as to why I can't reboot from a command-R, that would be greatly appreciated.

Does anyone think this may be a bad disc, with a sector holding the operating system perhaps involved?

 

[lindycorp]

When you have the external connected, go into Disk Utility on the internal drive, select by highlighting and run Repair Disk over it and see what is reported.

Harry, it sounds like you mean select the internal drive then repair disk. If I select the Macintosh HD internal disk, then repair disk is grayed out. Did you mean "verify disk?"

 

[lindycorp]

If I do a verify disk on the internal drive, I get a green font: "The volume Macintosh HD appears to be OK."

 

[lindycorp]

Same result for the Lacie Time Machine drive ...

 

[lindycorp]

Disconnected the time machine Lacie ... no difference ...

 

[harryb2448]

You have a backup suggest a clean install of Yosemite by erasing and formatting the internal drive.

One thought ~ where did you get the memory not from a PC shop I trust? Macs are very fussy about memory and mustv have dearer low density modules. PCs as a rule of thumb us cheaper high density which most shops only stock.

 

[Slydude]

I haven't had to use this in a while but Memtest OS X has found bad memory when other measures have failed.

Do you have a second user account on your Mac? If so, does the problem occur there? It might be worth creating a new account for testing purposes. You can do this from System Preferences>Users & Groups. Make it an administrator account and run from there for a while. Try not to add anything to the login items area. If the problem disappears that would suggest a software issue.

 

[lindycorp]

You have a backup suggest a clean install of Yosemite by erasing and formatting the internal drive.

Well, yes, but:
1) How do I know the integrity of the disc is intact -- doing all that just to find out the disc is bad would be a bummer. Can I assume that since the Disk Utility did not find any issues the disk is OK?

2) Why can't I get an install from the recovery portion of time machine, i.e., when I reboot with Command-R I get nothing (as previously described). Why is that?!

3) What in the world can I install from? I don't think I ever got disks with the machine and they'd be hopelessly outdated now anyway ????

BTW, memory was from Amazon and was I believe Crucial. I'm not thinking it's the memory as the problem pre-dated the memory upgrade, albeit resolved itself around that time only to resurface recently.

Thanks for hanging in there!

 

[harryb2448]

Reboot and hold down Option and see if that finds Recovery. Whn itopen leave the Installer, go to Utilities > Disk Utility and run Repair Disk and see what is reported. The best option was to burn Yosemite to a USB thumb drive prior to Installing. Installing removes it from the Applications Folder.

 

[MacInWin]

Problems with disk drives come in a variety of flavors. Disk Utility finds problems that are truly hard failures (bad sectors, etc), but misses the "softer" failures where the internal drive hardware is having to repeat read/write operations over and over before they succeed. Those kinds of failures are harder to detect, and the symptoms can be slower operations because each read/write takes longer to complete because of the re-tries. But because it ultimately succeeds, DU thinks it's OK. That slowing down is the reason that when folks say the machine gets slow we tend to think the HD is failing (not failed, just failing). Given the price of HDs these days, it's easier to jump to "replace the HD" than to spend a lot of time/effort doing other things.

All that said, the answer to question #1 is "you can't really KNOW, but you can try." Reformatting and reinstalling SHOULD find failing drives, but there isn't any guarantee.

Question #2. There is no recovery partition on TM backups. They are not bootable. The Recovery Partition is on your internal drive, invisible to you until you boot holding down CMD + R. If there is a recovery partition, you'll be offered the opportunity to select it. NOTE: you have to hold the CMD+R until the options appear, not just hold for a few seconds.
3. Assuming NO recovery partition and NO bootable clone, you can boot holding CMD+I and do an Internet recovery. Apple will install the OS that came with the machine and then you can apply/reinstall whatever version you had, or restore from the TM backup. Was the memory specifically for YOUR machine? Crucial sells good memory, usually, but it's up to you to make sure it's the memory for YOUR machine. So the memory could be GOOD but WRONG.

Harry's last post was a bit abbreviated. You don't actually burn Yosemite to a USB, you copy a file named "Install OS X Yosemite.app" to the USB. Or, if you want it bootable from that USB, get Diskmaker X and use that to create a bootable USB stick that will do the install for you if needed. You need to do that BEFORE installing Yosemite because as part of the install, it deletes "Install OS X Yosemite.app" from your drive. Diskmaker X is here.

 

[lindycorp]

Reboot and hold down Option and see if that finds Recovery. Whn itopen leave the Installer, go to Utilities > Disk Utility and run Repair Disk and see what is reported. The best option was to burn Yosemite to a USB thumb drive prior to Installing. Installing removes it from the Applications Folder.

Eureka, when I held down Option and rebooted, it actually did find a Recovery disc. I got the option to boot from a recovery disk titled 10.10.recovery or something similar, or the regular Macintosh disk.

I was so fascinated I clicked on Recovery, let it run a few seconds, but nothing really happened. Not sure what was going to come next or if I would even be able to boot, I just did a hard restart and booted normally.

Are you saying to launch Recovery, then cancel out? How exactly am I supposed to "leave the installer ... and ... "go to Utilities" ... I would expect that once the installer starts it will start an OS install. My experience has been that once that type of process begins there's kind of "no going back" (hence my cancel out since I was not prepared for a 3 hour tour).

Can you be more specific? Also, if I really have the opportunity to reinstall the OS, why not just end this pain and go for it instead of wasting more time in DU?

Towards that end, how am I supposed to use this recovery partition to get a functioning OS again? Is it going to install something 18 months old then I do 57 updates to come up to speed, like Win-Doze does it?

Tnx, Paul

 

[Slydude]

Give this a quick read. I think it will explain things. It pre-dates Yosemite but the process hasn't really changed since this was written. Mac Recovery HD Volume: Reinstall OS X or Troubleshoot