Slow boot time after update to Mojave - External SSD

Yes, I did and now it boots fast again.

I did a Time Machine backup into the internal drive, erased drive to HFS and reinstalled from Time Machine. A couple hours and working again.

Northern315, I had a similar issue, was booting on the internal drive where I have a reminiscence of macOS something 🙂 Try this: boot into Mojave, go to Settings -> Startup Disk , unlock the modifications option then select your Mojave disk, then click on the small Restart... button that you have in the right side. This fixed my issue with not booting into Mojave/External SSD. Now I still boot in 1000 years, but at least I dont have to choose the disk everytime.

Hope this helps.

Hi,

i had similar issues with an iMac and a MacBook pro booting forever. I found a solution within a german board.

I use LittleSnitch on both machines and after uninstall both machines run as fast as expected prior to High Sierra performance.

So if you run Little Snitch try this one out. I informed the Developer of Little Snitch about this boot delay.

cheers

Boris

For those interesting if trim adds a delay at boot time, issue the following command in the Terminal:

log show --predicate 'eventMessage BEGINSWITH "spaceman"' --last boot

TRIM works only on internal and Thuderbolt drives. But even for USB drives kernel scans for free blocks and as it seems try to send trim command.

Here is an example when my SSD was in USB case:

spaceman_trim_free_blocks:3245: scan took 0.072297 s, trims took 0.000000 s

Then in the Thunderbolt case with disabled trim (almost the same as USB):

After the "sudo trimforce enable" command, there was ~25 sec. delay at boot:

Today, log shows very little delay at boot:

I have decided to go another way now. I am now heavily using the Sleepmode instead of shutting down and restarting my iMac, so I only reboot quite rarely now. Using AppleScript, I have written myself two small shell scripts that reside on my desktop for quick access. One enables the "Allow drives to enter sleep mode" option within energy settings and then sends my iMac directlly into Sleepmode. After waking it up again later, I start the other script which simply disables the aforementioned option (because I don't like any of my drives going into sleep mode while the machine is on). Using these two scripts eliminates the tedious need of entering the password each time you change that option and saves some mouse clicking.

I have also permanently disabled the "Power Nap" option and the "Wake up on network activity" option in order for my iMac to do absolutely NOTHING while in Sleepmode. So I think my Sleepmode configuration is the closest you can get to fully shutting down - but at the same time, I now have zero boot time when waking the iMac up again. The iMac and the external SSD stay completely cold while in Sleepmode, no sound is heard. And I can use the keyboard to start my iMac instead of having to use the rear button ;-))

For me, this is the best way to go while waiting for Apple to fix this issue, but as someone else has already said, my hopes for an Apple fix start to vanish too... on the other hand, I don't want to switch back to HFS+ and I am not willing to spend about 150 Euros for the Thunderbolt solution either just to reduce boot times back to normal.

I have an iMac 5K 2017 with 32GB RAM and 3TB fusion internal HDD with no USB boodting and still experienced Mojave slow starts and more annoyingly slow waking up from sleep (each wake up is a wait of a minute). Before Mojave all was pretty instantenous.

Looking at this thread I had a go and removed Paragon NTFS software I had (latest version 15.1.x updated for Mojave) and it worked. My boot times are as fast as in Sierra before and waking up from sleep are instanteneous. I think people do have to try to eradicate all 3rd party software/drivers from the system especially when slow boot times have not much to do with USB SSD like mine.

I did a fresh MacOS install (no 3rd party software at all) and I still had this problem.

As I mentioned earlier, I fixed this by cloning an existing MacOS installation files to a HFS+ preformatted drive. I have been using this for some time now and it is working without any issues every day (touches wood). But again, I did this at my own risk and I don’t mind if this hard drive fails – I have backups and I use cloud providers along with local NAS server.

I wanted to ask has anyone opened their iMac and replaced the existing internal HDD with a Samsung SSD? Can someone who has done this please comment if they are affected by this? Am I right in thinking that this is a USB-only bug?

Nope. It's not specific to Mojave... Mine started on High Sierra (Immediately after converting my external Samsung 860EVO in an Inteck USB3 enclosure to APFS). That was a 90 MINUTE boot.

Upgrading to Mojave didn't fix it. Neither did a Sandisk Extreme SSD (After the Mojave upgrade). Reformating the disks to APFS (As opposed to converting them to APFS) resulted in a mere 90 SECOND boot time.. Still too slow.

Having Windoze on the Samsung increases the boot time (again) to about 10 minutes.

The delay (For me) is in the firmware. Not the OS. You can see that also if you enable verbose on the mac boot (-v). The delay is all BEFORE the OS boots.

Yes, the bug is fixed only in the BETA 2, I updated this morning after having the boot delay for couple of weeks.

cheers

Boris

Hi.

You can restore any point saved in TimeMachine.

I install Mojave on september24 and i kept making backups in TimeMachine.

Yesterday I restored the iMac with a backup of September 23 and returned to Hight Sierra whithout problems.

Here's a weird one: Even though I didn't have Paragon ntfs installed anymore it turns out there was still a Paragon service left in my Launchctl. Removed that and my boot time has improved considerably.. 😕

I did enable trim, but noticed that it took 25 sec. at next startup. You can look at console.log to see how long is trim taking at boot time. To do so, after the boot you need to collect the log info in a file. I use similar to this command:

sudo log collect --output ~/Documents/log.logarchive --last 1h

Then double click on the produced log.logarchive file in your Documents folder, show "All Messages" and search for "spaceman" or "trim". Log command has a "show" switch, but I'm not familiar how to use it, yet.

With trim disabled it takes 0 sec., but it shows thousands of blocks awaiting trim. So, I will look if that slows down boot process too much and will disable trim.

Hi guys, I decided to try the suggestion from the other Alex because I have set up my Macbook the way I want it and I thought it would be nice if I could simply clone all my Apps, Settings, Files, etc to the SSD.

Bottom line: it worked. My total boot time is now 45 seconds (with APFS it is 2 and and 25secs).

Please note that I don’t keep any important data on my SSD, so I am not warried about it crashing. I also feel that the fact that Apple used HFS+ for so many years means that it will likely continue to work at least for a few more years.

But again, I did this at my own risk and I do realise that this is not officially supported.

@grdh20 - Would you please, specify your TB3 enclosure. USB-C connector looks like Thunderbolt v3, but connection is only USB. Thunderbolt drives are listed under "SATA /SATA Express" section of System Information with these fields:

Medium Type: Solid State

Removable Media: No

TRIM Support: Yes/No

S.M.A.R.T. status: Verified

It’s not USB or any other connection problem. I’m not going to repeat repeat my previous lengthy posts but the fact that you can work around the issue and get fast boot up by cloning a Mojave system from Apple HDD to HFS+ formatted SSD connected via USB proves that. I know that’s not supported by Apple and some posters advise strongly agsbut... it has worked for me for weeks now.