Netty Webclient memory leak in spring boot [duplicate]

Question

Hi all we are seeing app crash under heavy load when we analyze our heap dump major memory is taken by netty below the following leak suspect

218,618,256 bytes (63.15 %) of Java heap is used by 24 instances of io/netty/buffer/PoolArena$HeapArena
 Contains 12 instances of the following leak suspects:
 - byte[] holding 16,777,224 bytes at 0x711b00000
 - byte[] holding 16,777,224 bytes at 0x710a00000
 - byte[] holding 16,777,224 bytes at 0x70ea00000
 - byte[] holding 16,777,224 bytes at 0x708500000
 - byte[] holding 16,777,224 bytes at 0x70d900000
 - byte[] holding 16,777,224 bytes at 0x70c800000
 - byte[] holding 16,777,224 bytes at 0x71ea00000
 - byte[] holding 16,777,224 bytes at 0x716c00000
 - byte[] holding 16,777,224 bytes at 0x715900000
 - byte[] holding 16,777,224 bytes at 0x705c00000
 - byte[] holding 16,777,224 bytes at 0x704b00000
 - io/netty/buffer/PoolChunk holding 33,609,288 bytes at 0x71d476ad8

we are using only 6 instance of webclient why it is showing 12 instance? why it is not releasing memory? can anyone guide us on this.

WebClient request

    public <T> Mono<T> sendGetRequest(String apiBaseUrl, String apiEndpoint, String queryParams, HttpHeaders headers, Class<T> clazz, Map<String, String> params) {
            return webClient.get()
                    .uri(apiBaseUrl + apiEndpoint, params).headers(getHttpHeaders(headers))
                    .retrieve()
                    .bodyToMono(clazz);
        }

Answer 1

This memory is allocated by netty and it's not a leak. See similar question: Memory accumulated in netty PoolChunk