Does your Mac OSX 10.9.4 Mavericks do a bad job at memory management? Use this script to force it to free some memory. Run it passing the amount of gigs of ram you have (default 8gb) and [optionally] wait the chart on the Memory tab of Activity Monitor to display some yellow and red.

purge.c

#if 0
BIN=`mktemp $0.bin.XXXX`
trap "rm -fv $BIN" 0
gcc -O3 $0 -Wall -Werror -o $BIN && $BIN $1
exit
#endif

#include<stdio.h>
#include<stdlib.h>

#define GB (1024*1024*1024)
#define CHUNK 256000000
int main(int argc, char *argv[])
{
    int i, j;
    int total = argc > 1 ? atoi(argv[1]) : 8;
    int n = ((long long)total * GB) / CHUNK;
    long long mem = 0;
    for(i=0; i<n; i++) {
        char *p = malloc(CHUNK);
        mem+=CHUNK;
        printf("%03d %p %0.1f/%dGB\n", i, p, mem/(double)GB, total);
        for(j=0; j<CHUNK; j++) {
            p[j] = i^j; // XXX avoid mavericks' compression
        }
    }
    return 0;
}