如何解决** mach_vm_map（size = 8388608）失败（错误代码= 3）***错误：无法分配区域错误

HI在我的应用程序我正在从服务器上下载文件，总文件大小超过9GB.After下载1GB数据应用程序崩溃，并显示错误** mach_vm_map（size = 8388608）失败（错误代码= 3）***错误：不能分配区域。 任何人都可以帮助我如何解决这个问题。

+(void)base64Decode:(NSData *)fData writeToFile:(NSFileHandle *)fHandle { unsigned char inBuffer[4] ; unsigned char outBuffer[3] ; NSRange part ; part.location = 0 ; part.length = 1 ; NSMutableData *oData = [[NSMutableData alloc] init] ; BOOL bInProgress = YES ; int i ; int total = 0 ; while ( bInProgress ) { inBuffer[0] = inBuffer[1] = inBuffer[2] = inBuffer[3] = 0 ; outBuffer[0] = outBuffer[1] = outBuffer[2] = 0 ; for ( i = 0 ; i < 4 ; ) { if ( [fData length] > part.location ) { [fData getBytes:inBuffer+i range:part] ; part.location++ ; if ( ( inBuffer[i] == 0x0d ) || ( inBuffer[i] == 0x0a ) ) continue ; else i++ ; } else { bInProgress = NO ; break ; } } // if ( i != 4 ) // { // NSLog ( @"Less\n" ) ; // } int unexpect = 0 ; for ( int j = 0 ; j < i ; j++ ) { if ( ( inBuffer[j] >= 'A' ) && ( inBuffer[j] <= 'Z' ) ) { inBuffer[j] -= 'A' ; } else { if ( ( inBuffer[j] >= 'a' ) && ( inBuffer[j] <= 'z' ) ) { inBuffer[j] -= 'a' ; inBuffer[j] += 26 ; } else { if ( ( inBuffer[j] >= '0' ) && ( inBuffer[j] <= '9' ) ) { inBuffer[j] -= '0' ; inBuffer[j] += 52 ; } else { if ( inBuffer[j] == '+' ) { inBuffer[j] = 62 ; } else { if ( inBuffer[j] == '/' ) { inBuffer[j] = 63 ; } else { #ifdef DEBUG NSLog ( @"fHandle Unexpected char: %c: %x\n", inBuffer[j], inBuffer[j] ) ; #endif unexpect++ ; } } } } } } i -= unexpect ; int len = (i * 6) / 8 ; if ( ( i * 6 ) % 8 ) len++ ; total += len ; outBuffer[0] = ( inBuffer[0] << 2 ) | ( ( inBuffer[1] & 0x30 ) >> 4 ); outBuffer[1] = ( ( inBuffer[1] & 0x0f ) << 4 ) | ( ( inBuffer[2] & 0x3c ) >> 2 ); outBuffer[2] = ( ( inBuffer[2] & 0x03 ) << 6 ) | ( ( inBuffer[3] & 0x3f ) ); [oData appendBytes:outBuffer length:len] ; if([oData length] > 1024*10) { NSError *error; BOOL dataWritten=[self writeData:oData toFileHandle:fHandle error:&error]; NSLog(@"dataWritten %hhd",dataWritten); if(oData) { [oData release]; oData = nil ; } //[oData release]; oData = [[NSMutableData alloc] init] ; } } //fwrite([oData bytes], 1, [oData length], fHandle) ; //[fHandle writeData:oData] ; NSError *error; [self writeData:oData toFileHandle:fHandle error:&error]; if(oData) { [oData release]; oData = nil ; } // NSLog ( @"Total written: %d\n", total ) ; } +(BOOL)writeData:(NSData *)data toFileHandle:(NSFileHandle *)fileHandler error:(NSError **)error { @try { [fileHandler writeData:data]; } @catch (NSException *e) { if (error != NULL) { NSDictionary *userInfo = @{ NSLocalizedDescriptionKey : @"Failed to write data", // Other stuff? }; *error = [NSError errorWithDomain:@"MyStuff" code:123 userInfo:userInfo]; } return NO; } return YES; } Here fileHandler is NSFileHandle *pdfPathHandle = [NSFileHandle fileHandleForWritingAtPath:filePath];