Live data from Hacker News

AWS vs. GCP reliability is wildly different

freeman.vc

41–50 of 245 posts

Re: AWS vs. GCP reliability is wildly different

#41
post #16

Earlier quoted context omitted.

GCP also had 84 errors compared to 1 for AWS

Maybe 1 reported. Not saying aws reliability is bad, but the number of various glitches that crop up in various aws services and not reflected on their status page is quite high.

Errors returned from APIs and the status page are completely separate topics in this context.

Re: AWS vs. GCP reliability is wildly different

#43
post #19

> The offerings between the two cloud vendors are also not the same, which might relate to their differing response times. GCP allows you to attach a GPU to an arbitrary VM as a hardware accelerator - you can separately configure quantity of the CPUs as needed. AWS only provisions defined VMs that have GPUs attached - the g4dn.x series of hardware here. Each of these instances are fixed in their CPU allocation, so if…

I wouldn't be surprised if GCP has GPUs scattered throughout the datacenter. If you happen to want to attach one, it has to find one for you to use - potentially live migrating your instance or someone else's so that it can connect them. It'd explain the massive variability between launch times.

Re: AWS vs. GCP reliability is wildly different

#44
> In total it scaled up about 3,000 T4 GPUs per platform

> why I burned $150 on GPUs

How do you rent 3000 GPUs over a period of weeks for $150? Were they literally requisitioning it and releasing it immediately? Seems like this is quite a unrealistic type of usage pattern and would depend a lot on whether the cloud provider optimises to hand you back the same warm instance you just relinquished.

> GCP allows you to attach a GPU to an arbitrary VM as a hardware accelerator

it's quite fascinating that GCP can do this. GPUs are physical things (!) do they provision every single instance type in the data center with GPUs? That would seem very expensive.

Re: AWS vs. GCP reliability is wildly different

#45
What would you expect? AWS is an org dedicated to giving customers what they want and charging them for it, while GCP is an org dedicated to telling customers what they want and using the revenue to get slightly better cost margins on Intel servers.

Re: AWS vs. GCP reliability is wildly different

#46

I wonder why someone would equate "instance launch time" with "reliability"... I won't go as far as calling it "clickbait" but wouldn't some other noun ("startup performance is wildly different") have made more sense?

Well, if your system elastically uses GPU compute and needs to be able to spin up, run compute on a GPU, and spin down in a predictable amount of time to provide reasonable UX, launch time would definitely be a factor in terms of customer-perceived reliability.

Re: AWS vs. GCP reliability is wildly different

#47
post #7

Earlier quoted context omitted.

Dunno about AWS, but GCP uses live migration, and will migrate your VM across physical machines as necessary. The disk volumes are all connected over the network, nothing really depends on the actual physical machine your VM is ran on.

Azure, AWS and GCP all have live migration. VMWare has it too.

Are you sure, because AWS consistently requires me to migrate to a different host. They go as far as shutting down instances, but don't do any kind of live migrations.

Re: AWS vs. GCP reliability is wildly different

#48

AWS normally has machines sitting idle just waiting for you to use. Thats why they can get you going in a couple of seconds. GCP on the other hand fills all machines with background jobs. When you want a machine, they need to terminate a background job to make room for you. That background job has a shutdown grace time. Usually thats 30 seconds. Sometimes, to prevent fragmentation, they actually need to shuffle aroun…

borg implements preemption but the delay to start VMs is not because they are waiting for a background task to clean up.

Re: AWS vs. GCP reliability is wildly different

#49
post #44

> In total it scaled up about 3,000 T4 GPUs per platform > why I burned $150 on GPUs How do you rent 3000 GPUs over a period of weeks for $150? Were they literally requisitioning it and releasing it immediately? Seems like this is quite a unrealistic type of usage pattern and would depend a lot on whether the cloud provider optimises to hand you back the same warm instance you just relinquished. > GCP allows you to a…

Unlikely. More likely they put your VM on a host with GPU attached, and use live migration to move workloads around for better resource utilization.

However, live-migration can cause impact to HPC workloads.

Post reply on HN