[BUG] Salt Proxy 3003.2 memory leak issue

Description
Related to closed bug #58813
Despite running the latest version of Salt, a memory leak still persists in the Salt Proxy component.
As I need to run multiple salt proxy processes (6500), this memory issue is exacerbated and quite severe.

Setup

• Server Configuration - VM running on Cloud Service (64 CPU's 256 GB RAM) - CentOS 7
• Proxies - 1300 proxies per VM. 5 VM's in total to support required density - 6500 proxy minions
• Architecture - 1 central Salt master with x5 syndic masters running locally on the VM where proxies reside
• Proxy Configuration:

master: 127.0.0.1
master_tries: -1
auth_tries: 7
cache_jobs: False

multiprocessing: False

log_level: quiet

# DNS
retry_dns: 60
retry_dns_count: 5

# Internal Timers
acceptance_wait_time: 10
random_reauth_delay: 60
auth_timeout: 60
random_startup_delay: 30

# Grains Configuration
grains_cache: False
grains_deep_merge: True
# grains_cache_expiration: 5400
# grains_refresh_every: 60

grains_blacklist:
  - dns
  - cpuarch
  - hwaddr_*
  - kernel*
  - locale_info
  - mem_total
  - gpu*
  - num_gpus
  - ip[46]
  - osarch
  - osfinger
  - osfullname
  - osrelease
  - osrelease_info
  - virtual
  - zmq*

enable_gpu_grains: False

# Mine Configuration
mine_enabled: False
#mine_return_job: False
#mine_interval: 60

Steps to Reproduce the behavior
start 1..n proxy minions

Expected behavior
The proxy does not endlessly consume resources, instead runs with a stable amount. I believe something like 500Mb is considered the norm.

Screenshots

Versions Report

Salt Version:
          Salt: 3003.2
 
Dependency Versions:
          cffi: 1.14.5
      cherrypy: Not Installed
      dateutil: 2.8.1
     docker-py: 4.4.4
         gitdb: Not Installed
     gitpython: Not Installed
        Jinja2: 2.11.3
       libgit2: Not Installed
      M2Crypto: 0.35.2
          Mako: Not Installed
       msgpack: 0.6.2
  msgpack-pure: Not Installed
  mysql-python: Not Installed
     pycparser: 2.20
      pycrypto: Not Installed
  pycryptodome: 3.10.1
        pygit2: Not Installed
        Python: 3.6.8 (default, Nov 16 2020, 16:55:22)
  python-gnupg: Not Installed
        PyYAML: 5.4.1
         PyZMQ: 17.0.0
         smmap: Not Installed
       timelib: Not Installed
       Tornado: 4.5.3
           ZMQ: 4.1.4
 
System Versions:
          dist: centos 7 Core
        locale: UTF-8
       machine: x86_64
       release: 3.10.0-1160.36.2.el7.x86_64
        system: Linux
       version: CentOS Linux 7 Core