I got a fatal error reading a file that was too big to fit in a buffer.
FATAL ERROR: v8::Object::SetIndexedPropertiesToExternalArrayData() length exceeds max acceptable value
Or,
RangeError: "size" argument must not be larger than 2147483647
at Function.Buffer.allocUnsafe (buffer.js:209:3)
If I try to allocate a 1GB Buffer I get the same fatal Error,
var oneGigInBytes = 1073741824;
var my1GBuffer = new Buffer(oneGigInBytes); //Crash
What is the maximum size of a Node.js Buffer class instance?
Maximum length of a typed array in V8 is currently set to kSmiMaxValue which depending on the platform is either:
1Gb - 1byte on 32-bit
2Gb - 1byte on 64-bit
Relevant constant in the code is v8::internal::JSTypedArray::kMaxLength (source).
V8 team is working on increasing this even further on 64-bit platforms, where currently ArrayBuffer objects can be up to Number.MAX_SAFE_INTEGER large (2**53 - 1). See bug 4153.
This is now documented as part of Node's buffer api, the maximum size is buffer.constants.MAX_LENGTH.
buffer.constants.MAX_LENGTH <integer> The largest size allowed for a single Buffer instance.
On 32-bit architectures, this value is (2^30)-1 (~1GB).
On 64-bit architectures, this value is (2^31)-1 (~2GB).
This value is also available as buffer.kMaxLength.
So you can figure out how big it is by doing
> (require('buffer').constants.MAX_LENGTH + 1) / 2**30
2
Seems like the current max buffer size is 2147483647 bytes aka 2.147GB
Source: https://stackoverflow.com/a/44994896/3973137 (and my own code)
The actual maximum size of a buffer changes across platforms and
versions of Node.js. You can find out what's the limit
in bytes in a given platform, run this:
import buffer from "buffer";
console.log(buffer.constants.MAX_LENGTH);
Related
I am trying to reproduc a problem .
My c code giving SIGABRT , i traced it back to this line number :3174
https://elixir.bootlin.com/glibc/glibc-2.27/source/malloc/malloc.c
/* Little security check which won't hurt performance: the allocator
never wrapps around at the end of the address space. Therefore
we can exclude some size values which might appear here by
accident or by "design" from some intruder. We need to bypass
this check for dumped fake mmap chunks from the old main arena
because the new malloc may provide additional alignment. */
if ((__builtin_expect ((uintptr_t) oldp > (uintptr_t) -oldsize, 0)
|| __builtin_expect (misaligned_chunk (oldp), 0))
&& !DUMPED_MAIN_ARENA_CHUNK (oldp))
malloc_printerr ("realloc(): invalid pointer");
My understanding is that when i call calloc function memory get allocated when I call realloc function and try to increase memory area ,heap is not available for some reason giving SIGABRT
My another question is, How can I limit the heap area to some bytes say, 10 bytes to replicate the problem. In stackoverflow RSLIMIT and srlimit is mentioned but no sample code is mentioned. Can you provide sample code where heap size is 10 Bytes ?
How can I limit the heap area to some bytes say, 10 bytes
Can you provide sample code where heap size is 10 Bytes ?
From How to limit heap size for a c code in linux , you could do:
You could use (inside your program) setrlimit(2), probably with RLIMIT_AS (as cited by Ouah's answer).
#include <sys/resource.h>
int main() {
setrlimit(RLIMIT_AS, &(struct rlimit){10,10});
}
Better yet, make your shell do it. With bash it is the ulimit builtin.
$ ulimit -v 10
$ ./your_program.out
to replicate the problem
Most probably, limiting heap size will result in a different problem related to heap size limit. Most probably it is unrelated, and will not help you to debug the problem. Instead, I would suggest to research address sanitizer and valgrind.
In 2018 a Tech Lead at Google said they were working to "support buffers way beyond 4GiB" in V8 on 64 bit systems. Did that happen?
Trying to load a large file into a buffer like:
const fileBuffer = fs.readFileSync(csvPath);
in Node v12.16.1 and getting the error:
RangeError [ERR_FS_FILE_TOO_LARGE]: File size (3461193224) is greater than possible Buffer: 2147483647 bytes.
and in Node v14.12.0 (latest) and getting the error:
RangeError [ERR_FS_FILE_TOO_LARGE]: File size (3461193224) is greater than 2 GB
Which looks to me to be a limit set due to 32 bit integers for addressing of the buffers. But I don't understand why this would be a limitation on 64 bit systems... Yes I realize I can use streams or read from the file at a specific address, but I have massive amounts of memory laying around, and I'm limited to 2147483647 bytes because Node is limited at 32 bit addressing?
Surely having a buffer of a high frequency random access data-set fully loaded into a buffer rather than streamed has performance benefits. The code involved in directing the request to pull from the multiple buffer alternative structure is going to cost something, regardless of how small...
I can use the --max-old-space-size=16000 flag to increase the maximum memory used by Node, but I suspect this is a hard-limit based on the architecture of V8. However I still have to ask since the tech lead at Google did claim they were increasing the maximum buffer size past 4GiB: Is there any way in 2020 to have a buffer beyond 2147483647 bytes in Node.js?
Edit, relevant tracker on the topic by Google, where apparently they were working on fixing this since at least last year: https://bugs.chromium.org/p/v8/issues/detail?id=4153
Did that happen?
Yes, V8 supports very large (many gigabytes) ArrayBuffers nowadays.
Is there any way to have a buffer beyond 2147483647 bytes in Node.js?
Yes:
$ node
Welcome to Node.js v14.12.0.
Type ".help" for more information.
> let b = Buffer.alloc(3461193224)
undefined
> b.length
3461193224
That said, it appears that fs.readFileAsync has its own limit: https://github.com/nodejs/node/blob/master/lib/internal/fs/promises.js#L5
I have no idea what it would take to lift that. I suggest you file an issue on Node's bug tracker.
FWIW, Buffer has yet another limit:
> let buffer = require("buffer")
undefined
> buffer.kMaxLength
4294967295
And again, that's Node's decision, not V8's.
Is there a way to get the occupied memory size in bytes of BigInt numbers?
let a = BigInt(99999n)
console.log(a.length) // yield undefined
Thanks
V8 developer here. There is generally no way to determine the occupied memory size of an object, and BigInts are no exception. Why do you want to access it?
As far as the internal implementation in V8 is concerned, a BigInt has a small object header (currently two pointer sizes; this might change over time), and then a bit for every bit of the BigInt, rounded up to multiples of a pointer size. 99999 is a 17-bit number, so in your example let a = 99999n ("BigInt(99999n)" is superfluous!), the allocated BigInt will consume (2 + Math.ceil(17/64)) * 64 bits === 24 bytes on a 64-bit system.
It may or may not make sense to add length-related properties or methods (.bitLength?) to BigInts in the future. If you have a use case, I suggest you file an issue at https://github.com/tc39/proposal-bigint/issues so that it can be discussed.
AFAIK V8 has a known hard limit on the length of allowed Strings. Trying to parse >500MB Strings will pop the error:
Invalid String Length
Using V8 flags to increase the heap size doesn't make any difference
$ node --max_old_space_size=5000 process-large-string.js
I know that I should be using Streams instead. However is there any way to increase the maximum allowed String length anyway?
Update: Answer from #PaulIrish below indicates they upped it to 1GB - but it's still not user-configurable
In summer 2017, V8 increased the maximum size of strings from ~256MB to ~1GB. Specifically, from 2^28 - 16 to 2^30 - 25 on 64-bit platforms. V8 ticket.
This change landed in:
V8: 6.2.100
Chromium: 62.0.3167.0
Node.js: 9.0.0
Sorry, no, there is no way to increase the maximum allowed String length.
It is hard-coded in the source, and a lot of code implicitly relies on it, so while allowing larger strings is known to be on people's wishlist, it is going to be a lot of work and won't happen in the near future.
In Node.js 0.12.x maximum size of the buffer was limited by allocatable memory, which size could be got with:
require('smalloc').kMaxLength;
The actual value of kMaxLength was hardcoded in old versions of V8 and was equal to 0x3fffffff.
The problem is there is no smalloc module in io.js >=3.x (including node.js 4.x). It was mentioned that Buffer implementation was rewritten in V8 4.4.x.
So, my question is: is there a way to get the maximum size of the Buffer (and/or allocatable memory) in io.js >= 3.x ?
This file "calculated" (https://github.com/v8/v8-git-mirror/blob/4.4.63/src/objects.h) also has fixed constant for the external array.
4642 // Maximal acceptable length for an external array.
4643 static const int kMaxLength = 0x3fffffff;
EDIT:
It looks like you can use
require('buffer').kMaxLength;
That was the change in 3.0 and still in 4.0
b625ab4242 - buffer: fix usage of kMaxLength (Trevor Norris) #2003