Does anyone know, a way to minimize the container cold start time? Trying to get it to be 2-3 second

Does anyone know, a way to minimize the container cold start time? Trying to get it to be 2-3 seconds, but is right now 13 seconds. Thought I could make it smaller by reducing the image size and using buildx to create a optimized build for the linux/amd64 container runtime, but no luck

Code Cowboy•8/11/25, 5:24 AM

Is there a way to increase 2GB image size limit?

pandalambda2•8/11/25, 7:11 AM

how does outbound http requests work from a container? does the infra still smash on CF-Worker request header?

pandalambda2•8/11/25, 7:13 AM

and cf.worker.upstream_zone

Jjmickelly Hey, I just have a question around Cloudflare containers, does it support nested...

jmickelly•8/11/25, 9:34 AM

Is there an update to this?

pandalambda2•8/11/25, 12:30 PM

you would definitely expect this channel to be driving their FAQ and early feedback especially this early in the product launch, it's shame there seems to be little CF staff activity here

pandalambda2•8/11/25, 12:30 PM

each time I read the docs I end up with more questions than I started

Sscotto Any help @kian ?

kian•8/11/25, 4:13 PM

It should be created as a normal API token under your account: https://dash.cloudflare.com/profile/api-tokens

CCode Cowboy Is there a way to increase 2GB image size limit? 😬

kian•8/11/25, 4:15 PM

basic

basic

and

standard

standard

instances should have 4GB limits - nothing higher available at the moment though

NnickGPT Does anyone know, a way to minimize the container cold start time? Trying to get...

kian•8/11/25, 4:18 PM

How are you measuring this - is it from a new deployment -> opening Worker or just an existing image being slow to start instances?

Kkian `basic` and `standard` instances should have 4GB limits - nothing higher availab...

Chaika•8/11/25, 4:19 PM

That should be just disk size that is increased and not image size, at least according to the docs https://developers.cloudflare.com/containers/platform-details/#limits

kian•8/11/25, 4:22 PM

I'll ask the team if the docs are outdated but I did ask about images :meowthinking:

kian•8/11/25, 4:25 PM

Docs need updating - image size scales with disk size.

Ppandalambda2 how does outbound http requests work from a container? does the infra still smas...

kian•8/11/25, 5:32 PM

It'll come from the IPs on https://www.cloudflare.com/en-gb/ips/ but otherwise no

CF-Worker

CF-Worker

behaviour.

pandalambda2•8/12/25, 12:53 AM

if there any patterns/practices how one could authenticate outbound requests from a container other than say mutual tls, the IPs are shared across everyone so that doesn't appear practical, is there any plan to support cf.worker.upstream_zone? perhaps unchaining outbound worker support from workers for platform to achieve this?

Hoa Luu•8/12/25, 8:43 AM

Hello everyone,
I want to build a container with Python for Cloudflare.
I have a crontab trigger set up to call the container on a schedule. However, when I try to build the container, I encounter an error.

Alexander Lewis•8/12/25, 11:50 AM

Has anyone come across this error when creating a custom instance? If I set the values of the custom instance to match a named instance, it works fine, but say I change vcpu to 1, this will happen?

Error rolling out application project-container due to an internal error (request id: undefined): VALIDATE_INPUT

AAlexander Lewis Has anyone come across this error when creating a custom instance? If I set the ...

kian•8/12/25, 1:18 PM

Do you have the right entitlements for 1 vCPU? I don’t believe that’s available on the general paid plan.

Kkian Do you have the right entitlements for 1 vCPU? I don’t believe that’s available ...

Alexander Lewis•8/12/25, 1:30 PM

Believe the account is on enterprise which assuming that should allow more vCPU allocation?

John Spurlock•8/12/25, 8:34 PM

hmm, wondering if egress from containers -> its associated DO is billed?

pandalambda2•8/13/25, 2:35 AM

I think it must be otherwise you just proxy everything and get free unlimited/egress?

pandalambda2•8/13/25, 2:35 AM

but then that does raise the question what about communication with KV, D1, queues, R2 etc.. ?

pandalambda2•8/13/25, 4:26 AM

can one tail cloudflare container stdout/logs via wrangler do we need to do the click next dance on the web admin ui?

CCode Cowboy Wow @Eelco you are a legend, downgrading to 0.0.19 fixed local dev for me, supe...

kian•8/13/25, 9:43 PM

It looks like this was a change where the port in the URL (i.e 8787 for local Wrangler dev) started being used

kian•8/13/25, 9:44 PM

You should be able to use

.containerFetch(request, <port>)

.containerFetch(request, <port>)

.fetch(switchPort(request, <port>))

.fetch(switchPort(request, <port>))

HHoa Luu Hello everyone, I want to build a container with Python for Cloudflare. I have a...

gruntlord6•8/13/25, 10:22 PM

make sure you have the latest wrangler version, I had some weird permission errors on older versions

JJohn Spurlock hmm, wondering if egress from containers -> its associated DO is billed?

gruntlord6•8/13/25, 10:23 PM

thats kind of what I was wondering, and yea I am assuing it is or else you would just use the DO as a proxy

Ray Li•8/13/25, 11:19 PM

hi! Is there any examples of setting up pulumi with bindings for containers?

HHoa Luu Hello everyone, I want to build a container with Python for Cloudflare. I have a...

kian•8/14/25, 12:26 AM

gruntlord is right - that Wrangler version is older than when the Containers scope was added to the login command

henri•8/14/25, 2:16 AM

I'm having the same issue as described here @Mike Nomitch any news on the geographic
I just pushed a new version to my container, and it no longer starts. There are no logs available since the deployment, and requests to the container simply time out.

Hhenri I'm having the same issue as described here https://discord.com/channels/5953179...

kian•8/14/25, 2:40 AM

What's the application ID (UUID in the dashboard URL when you're viewing that Containers page)?

Kkian What's the application ID (UUID in the dashboard URL when you're viewing that Co...

henri•8/14/25, 2:41 AM

a0301d81-fc16-46c8-80ee-bee6d84073cc

kian•8/14/25, 2:51 AM

What does the instance list look like for you in the dashboard?

Kkian What does the instance list look like for you in the dashboard?

henri•8/14/25, 3:11 AM

I can see that there are two versions, it's running but I can't see any logs

kian•8/14/25, 3:11 AM

What are their IDs (and which is which)?

henri•8/14/25, 3:12 AM

there is only one instance, which has two versions, but the instante id should be the same, right?
anyway, here it is: 84d70fb446c123ff301da66929ea1aa10e9a2211820d7b760e03ac1efcb977ab

Ggruntlord6 thats kind of what I was wondering, and yea I am assuing it is or else you would...

John Spurlock•8/14/25, 1:39 PM

I'll take the other side and suspect it is not billed, but we'll have to wait for someone on the team to weigh in

JJohn Spurlock I'll take the other side and suspect it is _not_ billed, but we'll have to wait ...

gruntlord6•8/14/25, 1:47 PM

I would love that to be the case so I hope I am wrong, I think paying egress from cloudflare to cloudflare is insane

Hhenri there is only one instance, which has two versions, but the instante id should b...

kian•8/14/25, 2:17 PM

The team couldn't find any issues in the logs & it seemed to be healthy to them - are you still having the issue?

CD_CNTNew•8/15/25, 8:50 AM

Anyone come across containers become harder and harder to be active after several times of successful startup&stop, mostly with "no container instance" or "not listening on TCP" errors? On the dashboard, the logs show containers seem like never get requests from workers to wake up.

CCD_CNTNew Anyone come across containers become harder and harder to be active after severa...

gruntlord6•8/15/25, 6:25 PM

I haven't. I have an image processing container so that I can use sharp to batch convert images and store them in R2. I start it up frequently, upload more images, start it up again to do those etc.

what is you use case where this occurs?

gruntlord6•8/15/25, 11:52 PM

is there a way to see billable container usage?

Ggruntlord6 I haven't. I have an image processing container so that I can use sharp to batch...

CD_CNTNew•8/16/25, 3:15 AM

Just normal http backend in the containers, stateless even. Thought it's a simple usecase for testing the containers on cloudflare, but never thought what happened like this. I guess containers never got requests from workers or durable objects bound with them, sort of bugs?

gruntlord6•8/16/25, 3:16 AM

sorry I'm not really following, you have a web service running from the container directly and it never responds?

CD_CNTNew•8/16/25, 3:17 AM

actually never start up I think. Once start up successfully, they can respond quite well

gruntlord6•8/16/25, 3:18 AM

it should start as soon as you run the attached durable object

CD_CNTNew•8/16/25, 3:19 AM

yes, at the begining just deployed, they worked well but after several times start and stop, they appeared harder to wake again

gruntlord6•8/16/25, 3:20 AM

no idea, I've even had 10 instances running for the same job without any issues starting them and stopping them

CD_CNTNew•8/16/25, 3:21 AM

how about the sleepafter of your containers?

gruntlord6•8/16/25, 3:21 AM

although I always communicate with the durable objects associated with the container

Does anyone know, a way to minimize the container cold start time? Trying to get it to be 2-3 second

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