Django的 - 在POST解析表单集数据是十分缓慢

Question

我有一个模型：

class IP(models.Model): 
    address  = models.GenericIPAddressField() 
    fqdn  = models.CharField(max_length=255, blank=True) 
    description = models.CharField(max_length=1000, blank=True) 
    available = models.BooleanField(default=True) 
    reserved = models.BooleanField(default=False) 
    network  = models.ForeignKey(Network, on_delete=models.CASCADE) 
    customer = models.ForeignKey(Customer,on_delete=models.CASCADE, blank=True, null=True) 

和一种形式：

class IPForm(ModelForm): 
    id   = forms.CharField(widget=forms.HiddenInput()) 
    address  = forms.CharField(disabled=True, 
            widget=forms.TextInput(attrs={'class':'  form-control'})) 
    fqdn  = forms.CharField(widget=forms.TextInput(attrs={'class':'  form-control'}), required=False) 
    description = forms.CharField(widget=forms.TextInput(attrs={'class':'  form-control ip_description'}), required = False) 
    customer = forms.ModelChoiceField(queryset=Customer.objects.all().order_by('name'), widget=forms.Select(attrs={'class':'form-control'}), required=False) 
    reserved = forms.BooleanField(widget=forms.CheckboxInput(attrs= {'class':'checkbox'}), required=False) 
    class Meta: 
     model = IP 
     exclude = ['available', 'network'] 

和一个观点，即创建具有modelformset_factory一个formset：

def ipDetailView(request, ipIDs=None): 
    ipformset = modelformset_factory(IP, form=IPForm, extra=0) 
    if request.method == 'POST': 
     if len(request.POST.getlist('ip')): 
      #we were sent a list of IP IDs to edit 
      if 'clear_btn' in request.POST: 
       #just remove the fqdn/description of the posted IPs 
       ips = IP.objects.filter(id__in=request.POST.getlist('ip')) 
       for ip in ips: 
        ip.fqdn = '' 
        ip.description = '' 
        ip.available = True 
        ip.save() 
       return redirect ('iplistview', networkID=ips[0].network.id) 
      else: 
       #post the forms so the IPs can be edited 
       formset =  ipformset(queryset=IP.objects.filter(id__in=request.POST.getlist('ip'))) 
       return render (request, 'ipmanager/ipdetailview.html',  {'formset' : formset}) 
     else: 
      #we were sent a set of IP forms to commit changes for 
      formset = ipformset(request.POST) 
      if formset.is_valid(): 
       instances = formset.save() 
       return redirect ('iplistview',  networkID=instances[0].network.id) 
      else: 
       return render(request, 'ipmanager/ipdetailview.html', 
               { 
               'formset'  : formset, 
               }) 

    else: 
     network = IP.objects.filter(id=ipIDs)[0].network 
     formset = ipformset(queryset=IP.objects.filter(id=ipIDs)) 
     return render (request, 'ipmanager/ipdetailview.html', {'formset' :  formset, 'network' : network}) 

我的问题是，我提交IP提交表单更改的POST部分需要5-8秒才能提交，无论我是否犯1个IP或20的代码是那部分很简单：

 formset = ipformset(request.POST) 
    if formset.is_valid(): 
     instances = formset.save() 

我什至不知道如何去弄清楚为什么要花这么长。我没有那种似乎陷入其他类似问题的多对多关系。我该如何去弄清楚是什么导致了这里的缓慢？

Answer 1

您可以使用django-debug-toolbar来确定哪些查询花费最多的时间，原始SQL语句，调用它的代码的位置，以及EXPLAIN它。

它还可以检测可以避免的潜在重复查询。

要是你发现你有重复的查询，他们通常可使用select_related避免。