Anyone seeing latency issues in KV? - Cloudflare Developers

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usualdev

Uusualdev Anyone seeing latency issues in KV?

Chaika

C

Chaika•5/7/25, 8:47 PM

not really

Chaika

C

Chaika•5/7/25, 8:47 PM

the chart to the right of that is more interesting, how many cold reads do you have? Are you setting cacheTtl higher where you can/have a lot of infrequent keys?

Chaika

CChaika not really

usualdev

U

usualdevOP•5/7/25, 8:49 PM

Thanks @Chaika I'm not using cacheTtl, I will set it now and see.
this is my read status chart

usualdev

Uusualdev Thanks @Chaika I'm not using cacheTtl, I will set it now and see. this is my rea...

Chaika

C

Chaika•5/7/25, 8:50 PM

good amount of cold reads. KV only has two actual backing stores/locations, one us and one in the eu, it's then cached everywhere else. Cold reads are expensive
Raising cacheTtl at the cost of consistency can help if it fits your use, or in general aiming to hit a few frequent keys rather then many infrequent

yinxingmaiming6409

Y

yinxingmaiming6409•5/15/25, 7:18 AM

If you don't need workers and want to use KV, you can only use HTTP, right? The interface request limit is too low.

yinxingmaiming6409

Yyinxingmaiming6409 If you don't need workers and want to use KV, you can only use HTTP, right? The ...

Hello, I’m Allie!

H

Hello, I’m Allie!•5/15/25, 7:23 AM

Yes. KV is really meant to be used with Workers. In the event you don’t want your program logic on Workers, I would still recommend using a Worker to do the actual reads/writes against KV, as it should be a lot more performant than using the default HTTP API

yinxingmaiming6409

Y

yinxingmaiming6409•5/15/25, 7:26 AM

But it's really difficult for workers to restrict the development language

yinxingmaiming6409

Yyinxingmaiming6409 But it's really difficult for workers to restrict the development language

Hello, I’m Allie!

H

Hello, I’m Allie!•5/15/25, 1:30 PM

What do you mean?

Hello, I’m Allie!

HHello, I’m Allie!Yes. KV is really meant to be used with Workers. In the event you don’t want you...

alotabits

A

alotabits•5/15/25, 6:12 PM

Is this because of the connection overhead of using the HTTP API? And is it mitigated for writes if you’re using bulk writes?

thomasgauvin

T

thomasgauvin•5/16/25, 1:45 PM

Yes, it's actually because the HTTP API includes both control plane operations (create resources in Cloudflare) and data plane operations (write, read on KV for example). We're working on removing the API rate limits entirely because KV itself does not need to be rate limited

thomasgauvin

T

thomasgauvin•5/16/25, 1:46 PM

So today, if you use bulk operations, you can definitely do more operations against your KV namespace than with individual operations

thomasgauvin

Tthomasgauvin Yes, it's actually because the HTTP API includes both control plane operations (...

1984 Ford Laser

1

1984 Ford Laser•5/16/25, 10:26 PM

Is the removal of the API rate limit just for the KV endpoints? Or is there a more general discussion around removing that limit altogether

FlikTeoh

FFlikTeoh I fail to understand why are KV being limited to only being fast when there are ...

planet

P

planet•5/17/25, 1:13 PM

some people put the Cache API in front of KV to reduce read costs, and it's still very fast (not sure if faster tho)

planet

P

planet•5/17/25, 1:16 PM

use whatever works

planet

P

planet•5/17/25, 1:19 PM

use kv as the persistent backend that the cache api will pull from

FlikTeoh

FFlikTeoh You're right. Just couldn't figure out why still need the KV 😅

thomasgauvin

T

thomasgauvin•5/19/25, 3:05 PM

KV is the persistent source of truth for data for many developers. What are you using as your persistent store in your case?

thomasgauvin

T

thomasgauvin•5/21/25, 1:54 PM

If you have small data that can fit in Secrets or Workers Environment Variables that is static (changes to secrets and env vars require new deployments), then yes, that's a good solution

Alex Izydorczyk

A

Alex Izydorczyk•5/21/25, 8:54 PM

We are trying to decide if to adopt KV. Here is our scenario:

We're using their KV store alongside Cloudflare Workers to serve as a cache for some of our frequently queried postgres queries.
We're hitting the cache, directly from the browser by querying a worker's API endpoint
The average payload size is 250kb, but it's taking 300-400ms to respond

Alex Izydorczyk

A

Alex Izydorczyk•5/21/25, 8:55 PM

is that expected performance? Not based on anything, I would have thought we'd get even faster performance

Alex Izydorczyk

A

Alex Izydorczyk•5/21/25, 8:55 PM

or is it possible we have misconfigured something

Alex Izydorczyk

AAlex Izydorczyk We are trying to decide if to adopt KV. Here is our scenario: - We're using the...

planet

P

planet•5/21/25, 10:01 PM

#hyperdrive better suited for this. tho 300-400ms for kv seems long

thomasgauvin

T

thomasgauvin•5/22/25, 4:09 PM

Hyperdrive is a good fit indeed @Alex Izydorczyk . But both Hyperdrive and Workers KV use the same caching layer. The difference is that Workers KV is persistent storage. If you write something to KV and access after it has been removed from cache (based on the cacheTtl parameter), you will be getting the value from KV's central stores https://developers.cloudflare.com/kv/concepts/how-kv-works/

thomasgauvin

Tthomasgauvin Hyperdrive is a good fit indeed @Alex Izydorczyk . But both Hyperdrive and Worke...

Alex Izydorczyk

A

Alex Izydorczyk•5/22/25, 4:17 PM

Not to throw my own engineer under the bus, but he says " Hyperdrive is just a connection pooler with a very light caching layer. It makes connecting to postgres quick yes, but not a true caching layer like KV." -- it sounds like we have some fundamental misunderstanding of the product difference?

1984 Ford Laser

1

1984 Ford Laser•5/27/25, 2:24 AM

Should I be seeing latency this high, even with mostly cold reads?

yinxingmaiming6409

Y

yinxingmaiming6409•5/28/25, 4:24 PM

Does the webrtc of CALL have to follow the SFU protocol? Data to CloudFlare servers, does everyone's connection consume data?

piffie

P

piffie•5/31/25, 7:33 AM

why is the write in batch function only available via rest API and not via the worker API? does not make sense.

whoami

W

whoami•6/9/25, 9:41 AM

how to import envenv from cloudflare:workerscloudflare:workers?
i am importing with import { env } from "cloudflare:workers" import { env } from "cloudflare:workers";
but got

⨯ cloudflare:workers
Module build failed: UnhandledSchemeError: Reading from "cloudflare:workers" is not handled by plugins (Unhandled scheme).
Webpack supports "data:" and "file:" URIs by default.
You may need an additional plugin to handle "cloudflare:" URIs.
Import trace for requested module:
cloudflare:workers

⨯ cloudflare:workers
Module build failed: UnhandledSchemeError: Reading from "cloudflare:workers" is not handled by plugins (Unhandled scheme).
Webpack supports "data:" and "file:" URIs by default.
You may need an additional plugin to handle "cloudflare:" URIs.
Import trace for requested module:
cloudflare:workers

anyone help me?

whoami

Wwhoami how to import `env` from `cloudflare:workers`? i am importing with` import { env...

XiNiHa

X

XiNiHa•6/9/25, 9:49 AM

Probably add cloudflare:workerscloudflare:workers to Webpack externals?

XiNiHa

X

XiNiHa•6/9/25, 9:50 AM

Not sure as we don't know how your app is built though, what framework are you using?

XiNiHa

XXiNiHa Not sure as we don't know how your app is built though, what framework are you u...

whoami

W

whoami•6/9/25, 9:51 AM

I am using nextjsnextjs, i just want to define a /api/test/api/test and call env.MY_KV.get("mykey")env.MY_KV.get("mykey") in /api/test/api/test?

whoami

Wwhoami I am using `nextjs`, i just want to define a `/api/test` and call `env.MY_KV.get...

XiNiHa

X

XiNiHa•6/9/25, 9:55 AM

Try adding the following to next.config.js

// or maybe export default? this may differ per environment
module.exports = {
  // ...other options
  webpack: (config) => {
    config.externals = ['cloudflare:workers'];
    return config
  }
}

// or maybe export default? this may differ per environment
module.exports = {
  // ...other options
  webpack: (config) => {
    config.externals = ['cloudflare:workers'];
    return config
  }
}

XiNiHa

X

XiNiHa•6/9/25, 9:56 AM

Let me know if you already have webpackwebpack option customized with your config

XiNiHa

XXiNiHa Let me know if you already have `webpack` option customized with your config

whoami

W

whoami•6/9/25, 10:02 AM

not work.

whoami

W

whoami•6/9/25, 10:02 AM

const nextConfig = {
  webpack: (config) => {
    config.externals = ["cloudflare:workers"];
    return config;
  },
};

export default nextConfig;

const nextConfig = {
  webpack: (config) => {
    config.externals = ["cloudflare:workers"];
    return config;
  },
};

export default nextConfig;

whoami

W

whoami•6/9/25, 10:02 AM

my next.config.mjsnext.config.mjs as above

whoami

W

whoami•6/9/25, 10:04 AM

my route.tsroute.ts is

import "server-only";
import { env } from "cloudflare:workers";

export async function POST(req: Request) {
  const url = new URL(req.url);
  const key = url.searchParams.get("key") || "testKey";
  const testValue = await env.QA_KVS.get(key);

  return new Response(testValue ?? "No value found", {
    headers: {
      "Content-Type": "text/plain",
    },
  });
}

import "server-only";
import { env } from "cloudflare:workers";

export async function POST(req: Request) {
  const url = new URL(req.url);
  const key = url.searchParams.get("key") || "testKey";
  const testValue = await env.QA_KVS.get(key);

  return new Response(testValue ?? "No value found", {
    headers: {
      "Content-Type": "text/plain",
    },
  });
}

XiNiHa

X

XiNiHa•6/9/25, 10:04 AM

Are you getting the same error?

whoami

W

whoami•6/9/25, 10:04 AM

the error message is

 ⨯ Error: Cannot find module 'cloudflare:workers'
Require stack:

 ⨯ Error: Cannot find module 'cloudflare:workers'
Require stack:

XiNiHa

XXiNiHa Are you getting the same error?

whoami

W

whoami•6/9/25, 10:05 AM

not the same

XiNiHa

X

XiNiHa•6/9/25, 10:05 AM

Eh then it looks like Next doesn't support the usecase

whoami

W

whoami•6/9/25, 10:06 AM

I am curious how cloudflare handles the kv request?

whoami

W

whoami•6/9/25, 10:07 AM

maybe we should have a sdk installed?

XiNiHa

X

XiNiHa•6/9/25, 10:07 AM

How are you deploying the Next app to Cloudflare?

XiNiHa

X

XiNiHa•6/9/25, 10:07 AM

Are you using next-on-pages or opennext?

XiNiHa

XXiNiHa How are you deploying the Next app to Cloudflare?

whoami

W

whoami•6/9/25, 10:08 AM

I am using this starter.

⨯ cloudflare:workers
Module build failed: UnhandledSchemeError: Reading from "cloudflare:workers" is not handled by plugins (Unhandled scheme).
Webpack supports "data:" and "file:" URIs by default.
You may need an additional plugin to handle "cloudflare:" URIs.
Import trace for requested module:
cloudflare:workers

⨯ cloudflare:workers
Module build failed: UnhandledSchemeError: Reading from "cloudflare:workers" is not handled by plugins (Unhandled scheme).
Webpack supports "data:" and "file:" URIs by default.
You may need an additional plugin to handle "cloudflare:" URIs.
Import trace for requested module:
cloudflare:workers

import "server-only";
import { env } from "cloudflare:workers";

export async function POST(req: Request) {
  const url = new URL(req.url);
  const key = url.searchParams.get("key") || "testKey";
  const testValue = await env.QA_KVS.get(key);

  return new Response(testValue ?? "No value found", {
    headers: {
      "Content-Type": "text/plain",
    },
  });
}

import "server-only";
import { env } from "cloudflare:workers";

export async function POST(req: Request) {
  const url = new URL(req.url);
  const key = url.searchParams.get("key") || "testKey";
  const testValue = await env.QA_KVS.get(key);

  return new Response(testValue ?? "No value found", {
    headers: {
      "Content-Type": "text/plain",
    },
  });
}